Heterocyclecarbonyl amino acid hydroxyethylamino sulfonamide retroviral protease inhibitors

ABSTRACT

Selected heterocyclecarbonyl amino acid hydroxyethylamino sulfonamide compounds are effective as retroviral protease inhibitors, and in particular as inhibitors of HIV protease. The present invention relates to such retroviral protease inhibitors and, more particularly, relates to selected novel compounds, composition and method for inhibiting retroviral proteases, such as human immunodeficiency virus (HIV) protease, prophylactically preventing retroviral infection or the spread of a retrovirus, and treatment of a retroviral infection.

RELATED CASE

[0001] This is a continuation-in-part of co-owned and co-pendingapplication Ser. No. 08/402,419, filed Mar. 10, 1995, which is acontinuation-in-part of co-owned and co-pending application Ser. No.08/392,305, filed Feb. 22, 1995, each of which is incorporated herein byreference in its entirety.

BACKGROUND OF THE INVENTION

[0002] The present invention relates to retroviral protease inhibitorsand, more particularly, relates to novel compounds, composition andmethod for inhibiting retroviral proteases, such as humanimmunodeficiency virus (HIV) protease. This invention, in particular,relates to heterocyclecarbonyl amino acid hydroxyethylamine sulfonamideprotease inhibitor compounds, composition and method for inhibitingretroviral proteases, prophylactically preventing retroviral infectionor the spread of a retrovirus, and treatment of a retroviral infection,e.g., an HIV infection. The subject invention also relates to processesfor making such compounds as well as to intermediates useful in suchprocesses.

[0003] During the replication cycle of retroviruses, gag and gag-polgene transcription products are translated as proteins. These proteinsare subsequently processed by a virally encoded protease (or proteinase)to yield viral enzymes and structural proteins of the virus core. Mostcommonly, the gag precursor proteins are processed into the coreproteins and the pol precursor proteins are processed into the viralenzymes, e.g., reverse transcriptase and retroviral protease. It hasbeen shown that correct processing of the precursor proteins by theretroviral protease is necessary for assembly of infectious virons. Forexample, it has been shown that frameshift mutations in the proteaseregion of the pol gene of HIV prevents processing of the gag precursorprotein. It has also been shown through site-directed mutagenesis of anaspartic acid residue in the HIV protease active site that processing ofthe gag precursor protein is prevented. Thus, attempts have been made toinhibit viral replication by inhibiting the action of retroviralproteases.

[0004] Retroviral protease inhibition typically involves atransition-state mimetic whereby the retroviral protease is exposed to amimetic compound which binds (typically in a reversible manner) to theenzyme in competition with the gag and gag-pol proteins to therebyinhibit specific processing of structural proteins and the release ofretroviral protease itself. In this manner, retroviral replicationproteases can be effectively inhibited.

[0005] Several classes of compounds have been proposed, particularly forinhibition of proteases, such as for inhibition of HIV protease. Suchcompounds include hydroxyethylamine isosteres and reduced amideisosteres. See, for example, EP O 346 847; EP O 342,541; Roberts et al,“Rational Design of Peptide-Based Proteinase Inhibitors, “Science, 248,358 (1990); and Erickson et al, “Design Activity, and 2.8 Å CrystalStructure of a C₂ Symmetric Inhibitor Complexed to HIV-1 Protease,”Science, 249, 527 (1990). U.S. Pat. No. 5,157,041, WO 94/04491, WO94/04492, WO 94/04493, WO 94/05639, WO 92/08701 and U.S. patentapplication Ser. No. 08/294,468, filed Aug. 23, 1994, (each of which isincorporated herein by reference in its entirety) for example describehydroxyethylamine, hydroxyethylurea or hydroxyethyl sulfonamide isosterecontaining retroviral protease inhibitors.

[0006] Several classes of compounds are known to be useful as inhibitorsof the proteolytic enzyme renin. See, for example, U.S. Pat. No.4,599,198; U.K. 2,184,730; G.B. 2,209,752; EP O 264 795; G.B. 2,200,115and U.S. SIR H725. Of these, G.B. 2,200,115, GB 2,209,752, EP O 264,795,U.S. SIR H725 and U.S. Pat. No. 4,599,198 disclose urea-containinghydroxyethylamine renin inhibitors. EP 468 641 discloses renininhibitors and intermediates for the preparation of the inhibitors,which include sulfonamide-containing hydroxyethylamine compounds, suchas3-(t-butoxycarbonyl)amino-cyclohexyl-1-(phenylsulfonyl)amino-2(5)-butanol.G.B. 2,200,115 also discloses sulfamoyl-containing hydroxyethylaminerenin inhibitors, and EP 0264 795 discloses certainsulfonamide-containing hydroxyethylamine renin inhibitors. However, itis known that, although renin and HIV proteases are both classified asaspartyl proteases, compounds which are effective renin inhibitorsgenerally are not predictive for effective HIV protease inhibition.

BRIEF DESCRIPTION OF THE INVENTION

[0007] The present invention relates to selected retroviral proteaseinhibitor compounds, analogs and pharmaceutically acceptable salts,esters and prodrugs thereof. The subject compounds are characterized asheterocyclecarbonyl amino acid hydroxyethylamine sulfonamide inhibitorcompounds. The invention compounds advantageously inhibit retroviralproteases, such as human immunodeficiency virus (HIV) protease.Therefore, this invention also encompasses pharmaceutical compositions,methods for inhibiting retroviral proteases and methods for treatment orprophylaxis of a retroviral infection, such as an HIV infection. Thesubject invention also relates to processes for making such compounds aswell as to intermediates useful in such processes.

DETAILED DESCRIPTION OF THE INVENTION

[0008] In accordance with the present invention, there is provided aretroviral protease inhibiting compound of the formula:

[0009] or a pharmaceutically acceptable salt, prodrug or ester thereof,wherein n represents 0 or 1;

[0010] R¹ represents alkyl, alkenyl, alkynyl, hydroxyalkyl, alkoxyalkyl,cyanoalkyl, imidazolylmethyl, —CH₂CONH₂, —CH₂CH₂CONH₂, —CH₂S(O)₂NH₂,—CH₂SCH₃, —CH₂S(O)CH₃, —CH₂S(O)₂CH₃, —C(CH₃)₂SCH₃, —C(CH₃)₂S(O)CH₃ or—C(CH₃)₂S(O)₂CH₃ radicals; preferably, R¹ represents alkyl of 1-5 carbonatoms, alkenyl of 2-5 carbon atoms, alkynyl of 2-5 carbon atoms,hydroxyalkyl of 1-3 carbon atoms, alkoxyalkyl of 1-3 alkyl and 1-3alkoxy carbon atoms, cyanoalkyl of 1-3 alkyl carbon atoms,imidazolylmethyl, —CH₂CONH₂, —CH₂CH₂CONH₂, —CH₂S(O)₂NH₂, —CH₂SCH₃,—CH₂S(O)CH₃, —CH₂S(O)₂CH₃, —C(CH₃)₂SCH₃, —C(CH₃)₂S(O)CH₃ or—C(CH₃)₂S(O)₂CH₃ radicals; more preferably, R¹ represents alkyl of 1-4carbon atoms, alkenyl of 2-3 carbon atoms, alkynyl of 3-4 carbon atoms,cyanomethyl, imidazolylmethyl, —CH₂CONH₂, —CH₂CH₂CONH₂, —CH₂S(O)₂NH₂,—CH₂SCH₃, —CH₂S(O)CH₃, —CH₂S(O)₂CH₃, —C(CH₃)₂SCH₃, —C(CH₃)₂S(O)CH₃ or—C(CH₃)₂S(O)₂CH₃ radicals; and most preferably, R¹ represents sec-butyl,tert-butyl, iso-propyl, 3-propynyl or —C(CH₃)₂S(O)₂CH₃ radicals;

[0011] R² represents alkyl, aralkyl, alkylthioalkyl, arylthioalkyl orcycloalkylalkyl radicals; preferably, R² represents radicals of alkyl of1-5 carbon atoms, aralkyl of 1-3 alkyl carbon atoms, alkylthioalkyl of1-3 alkyl carbon atoms, arylthioalkyl of 1-3 alkyl carbon atoms orcycloalkylalkyl of 1-3 alkyl carbon atoms and 3-6 ring member carbonatoms; more preferably, R² represents radicals of alkyl of 3-5 carbonatoms, arylmethyl, alkylthioalkyl of 1-3 alkyl carbon atoms,arylthiomethyl or cycloalkylmethyl of 5-6 ring member carbon atomsradicals; even more preferably, R² represents isobutyl, n-butyl,CH₃SCH₂CH₂—, benzyl, phenylthiomethyl, (2-naphthylthio)methyl, 4-methoxyphenylmethyl, 4-hydroxyphenylmethyl, 4-fluorophenylmethyl orcyclohexylmethyl radicals; even more preferably, R² represents benzyl,4-fluorophenylmethyl or cyclohexylmethyl radicals; most preferably, R²represents benzyl;

[0012] R³ represents alkyl, cycloalkyl or cycloalkylalkyl radicals;preferably, R³ represents radicals of alkyl radical of 1-5 carbon atoms,cycloalkyl of 5-8 ring members or cycloalkylmethyl radical of 3-6 ringmembers; more preferably, R³ represents propyl, isoamyl, isobutyl,butyl, cyclopentylmethyl, cyclohexylmethyl, cyclohexyl or cycloheptylradicals; more preferably R³ represents isobutyl or cyclopentylmethylradicals;

[0013] R⁴ represents aryl, heteroaryl or heterocyclo radicals;preferably, R⁴ represents aryl, benzo fused 5 to 6 ring memberheteroaryl or benzo fused 5 to 6 ring member heterocyclo radicals; or

[0014] R⁴ represents a radical of the formula

[0015] wherein A and B each independently represent O, S, SO or SO₂;preferably, A and B each represent O;

[0016] R⁶ represents deuterium, alkyl or halogen radicals; preferably,R⁶ represents deuterium, alkyl of 1-5 carbon atoms, fluoro or chlororadicals; more preferably R⁶ represents deuterium, methyl, ethyl,propyl, isopropyl or fluoro radicals;

[0017] R⁷ represents hydrogen, deuterium, alkyl or halogen radicals;preferably, R⁷ represents hydrogen, deuterium, alkyl of 1-3 carbonatoms, fluoro or chloro radicals; more preferably, R⁷ representshydrogen, deuterium, methyl or fluoro radicals; or R⁶ and R⁷ eachindependently represent fluoro or chloro radicals; and preferably, R⁶and R⁷ each represent a fluoro radical; or

[0018] R⁴ represents a radical of the formula

[0019] wherein Z represents O, S or NH; and R⁹ represents a radical offormula

[0020] wherein Y represents O, S or NH; X represents a bond, O or NR²¹;

[0021] R²⁰ represents hydrogen, alkyl, alkenyl, alkynyl, aralkyl,heteroaralkyl, heterocycloalkyl, aminoalkyl, N-mono-substituted orN,N-disubstituted aminoalkyl wherein said substituents are alkyl oraralkyl radicals, carboxyalkyl, alkoxycarbonylalkyl, cyanoalkyl orhydroxyalkyl radicals; preferably, R²⁰ represents hydrogen, alkyl of 1to 5 carbon atoms, alkenyl of 2 to 5 carbon atoms, alkynyl of 2 to 5carbon atoms, aralkyl of 1 to 5 alkyl carbon atoms, heteroaralkyl of 5to 6 ring members and 1 to 5 alkyl carbon atoms, heterocycloalkyl of 5to 6 ring members and 1 to 5 alkyl carbon atoms, aminoalkyl of 2 to 5carbon atoms, N-mono-substituted or N,N-disubstituted aminoalkyl of 2 to5 alkyl carbon atoms wherein said substituents are radicals of alkyl of1 to 3 carbon atoms, aralkyl of 1 to 3 alkyl carbon atoms radicals,carboxyalkyl of 1 to 5 carbon atoms, alkoxycarbonylalkyl of 1 to 5 alkylcarbon atoms, cyanoalkyl of 1 to 5 carbon atoms or hydroxyalkyl of 2 to5 carbon atoms; more preferably, R²⁰ represents hydrogen, alkyl of 1 to5 carbon atoms, phenylalkyl of 1 to 3 alkyl carbon atoms,heterocycloalkyl of 5 to 6 ring members and 1 to 3 alkyl carbon atoms,or N-mono-substituted or N,N-disubstituted aminoalkyl of 2 to 3 carbonatoms wherein said substituents are alkyl radicals of 1 to 3 carbonatoms; and most preferably, R²⁰ represents hydrogen, methyl, ethyl,propyl, isopropyl, isobutyl, benzyl, 2-(1-pyrrolidinyl)ethyl,2-(1-piperidinyl)ethyl, 2-(1-piperazinyl)ethyl,2-(4-methylpiperazin-1-yl)ethyl, 2-(1-morpholinyl)ethyl,2-(1-thiamorpholinyl)ethyl or 2-(N,N-dimethylamino)ethyl radicals;

[0022] R²¹ represents hydrogen or alkyl radicals; preferably, R²¹represents hydrogen radical or alkyl radical of 1 to 3 carbon atoms;more preferably, R²¹ represents hydrogen or methyl radicals; and mostpreferably, R²¹ represents a hydrogen radical; or

[0023] the radical of formula —NR²⁰R²¹ represents a heterocyclo radical;preferably, the radical of formula —NR²⁰R²¹ represents a 5 to 6 ringmember heterocyclo radical; more preferably, the radical of formula—NR²⁰R²¹ represents pyrrolidinyl, piperidinyl, piperazinyl,4-methylpiperazinyl, 4-benzylpiperazinyl, morpholinyl or thiamorpholinylradicals; and

[0024] R²² represents alkyl or R²⁰R²¹N-alkyl radicals; preferably, R²²represents alkyl or R²⁰R²¹N-alkyl radicals wherein alkyl is 1 to 3carbon atoms; and more preferably, R²² represents alkyl radical of 1 to3 carbon atoms; and

[0025] preferably R⁴ represents phenyl, 2-naphthyl, 4-methoxyphenyl,4-hydroxyphenyl, 3,4-dimethoxy phenyl, 3-aminophenyl, 4-aminophenyl,benzothiazol-5-yl, benzothiazol-6-yl, 2-amino-benzothiazol-5-yl,2-(methoxycarbonylamino)benzothiazol-5-yl, 2-amino-benzothiazol-6-yl,2-(methoxycarbonylamino)benzothiazol-6-yl, 5-benzoxazolyl,6-benzoxazolyl, 6-benzopyranyl, 3,4-dihydrobenzopyran-6-yl,7-benzopyranyl, 3,4-dihydrobenzopyran-7-yl, 2,3-dihydrobenzofuran-5-yl,benzofuran-5-yl, 1,3-benzodioxol-5-yl, 2-methyl-1,3-benzodioxol-5-yl,2,2-dimethyl-1,3-benzodioxol-5-yl, 2,2-dideutero-1,3-benzodioxol-5-yl,2,2-difluoro-1,3-benzodioxol-5-yl, 1,4-benzodioxan-6-yl,5-benzimidazolyl, 2-(methoxycarbonylamino)benzimidazol-5-yl,6-quinolinyl, 7-quinolinyl, 6-isoquinolinyl or 7-isoquinolinyl radicals;more preferably, R⁴ represents phenyl, 2-naphthyl, 4-methoxyphenyl,4-hydroxyphenyl, benzothiazol-5-yl, benzothiazol-6-yl, benzoxazol-5-yl,2,3-dihydrobenzofuran-5-yl, benzofuran-5-yl, 1,3-benzodioxol-5-yl,2-methyl-1,3-benzodioxol-5-yl, 2,2-dimethyl-1,3-benzodioxol-5-yl,2,2-dideutero-1,3-benzodioxol-5-yl, 2,2-difluoro-1,3-benzodioxol-5-yl,1,4-benzodioxan-6-yl, 2-(methoxycarbonylamino) benzothiazol-5-yl,2-(methoxycarbonylamino)benzothiazol-6-yl or2-(methoxycarbonylamino)benzimidazol-5-yl radicals; and most preferably,R⁴ represents phenyl, 4-methoxyphenyl, 4-hydroxyphenyl,benzothiazol-5-yl, benzothiazol-6-yl, 2,3-dihydrobenzofuran-5-yl,benzofuran-5-yl, 1,3-benzodioxol-5-yl, 2-methyl-1,3-benzodioxol-5-yl,2,2-dimethyl-1,3-benzodioxol-5-yl, 2,2-dideutero-1,3-benzodioxol-5-yl,2,2-difluoro-1,3-benzodioxol-5-yl, 1,4-benzodioxan-6-yl,2-(methoxycarbonylamino)benzothiazol-6-yl or2-(methoxycarbonylamino)benzimidazol-5-yl radicals;

[0026] R¹⁰ represents hydrogen, alkyl of 1-3 carbon atoms, benzyl,phenylmethoxycarbonyl, tert-butoxycarbonyl or4-methoxyphenylmethoxycarbonyl radicals; preferably R¹⁰ representshydrogen, methyl or benzyl radicals; more preferably R¹⁰ represents ahydrogen radical;

[0027] R¹¹ represents hydrogen, hydroxyalkyl or alkoxyalkyl radicals,wherein alkyl is 1-3 carbon atoms; preferably R¹¹ represents a hydrogenradical;

[0028] R¹² and R¹³ each independently represent hydrogen, hydroxy,alkoxy, 2-hydroxyalkoxy, hydroxyalkyl or alkoxyalkyl radicals;preferably, R¹² and R¹³ each independently represent hydrogen, hydroxy,alkoxy, 2-hydroxyethoxy, hydroxyalkyl or alkoxyalkyl radicals, whereinalkyl is 1-3 carbon atoms; more preferably, R¹² and R¹³ eachindependently represent hydrogen, hydroxy, methoxy or ethoxy radicals;or

[0029] R¹¹ and R¹² or R¹² and R¹³ along with the carbon atoms to whichthey are attached represent a benzo radical, which is optionallysubstituted with at least one hydroxy or alkoxy radical of 1-3 carbonatoms; preferably R¹¹ and R¹² along with the carbon atoms to which theyare attached represent a benzo radical, which is optionally substitutedwith at least one hydroxy or methoxy radical.

[0030] The absolute stereochemistry of the carbon atom of —CH(OH)— groupis preferably (R). The absolute stereochemistry of the carbon atom of—CH(R¹)— group is preferably (S). The absolute stereochemistry of thecarbon atom of —CH(R²)— groups is preferably (S).

[0031] A family of compounds of particular interest within Formula I arecompounds embraced by the formula

[0032] or a pharmaceutically acceptable salt, prodrug or ester thereof,wherein n, R¹, R², R³, R⁴ and R¹⁰ are as defined above.

[0033] A family of compounds of further interest within Formula II arecompounds embraced by the formula

[0034] or a pharmaceutically acceptable salt, prodrug or ester thereof,wherein n, R¹, R², R³, R⁴ and R¹⁰ are as defined above.

[0035] A more preferred family of compounds within Formula III consistsof compounds or a pharmaceutically acceptable salt, prodrug or esterthereof, wherein n represents 0;

[0036] R¹ represents sec-butyl, tert-butyl, iso-propyl, 3-propynyl or—C(CH₃)₂S(O)₂CH₃ radicals;

[0037] R² represents a benzyl radical;

[0038] R³ represents propyl, isoamyl, isobutyl, butyl, cyclohexyl,cycloheptyl, cyclopentylmethyl or cyclohexylmethyl radicals;

[0039] R⁴ is as defined above; and

[0040] R¹⁰ represents hydrogen, methyl or benzyl radicals.

[0041] Compounds of interest include the following:

[0042]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-3,3-dimethyl-butanamide;

[0043]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-3-methyl-butanamide;

[0044]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-3S-methyl-pentanamide;

[0045]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-4-pentynamide;

[0046]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[phenylsulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-3,3-dimethyl-butanamide;

[0047]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[phenylsulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-3-methyl-butanamide;

[0048]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[phenylsulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-3S-methyl-pentanamide;

[0049]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[phenylsulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-4-pentynamide;

[0050]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(4-methoxyphenyl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-3,3-dimethyl-butanamide;

[0051]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(4-methoxyphenyl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-3-methyl-butanamide;

[0052]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(4-methoxyphenyl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-3S-methyl-pentanamide;

[0053]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(4-methoxyphenyl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-4-pentynamide;

[0054]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(2,3-dihydrobenzofuran-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-3,3-dimethyl-butanamide;

[0055]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(2,3-dihydrobenzofuran-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-3-methyl-butanamide;

[0056]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(2,3-dihydrobenzofuran-5-yl)sulfonyl](2-methylpropyl)amino]-1S-phenylmethyl)propyl]-3S-methyl-pentanamide;

[0057]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(2,3-dihydrobenzofuran-5-yl)sulfonyl](2-methylpropyl)amino]-1S-phenylmethyl)propyl]-4-pentynamide;

[0058]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(benzothiazol-6-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-3,3-dimethyl-butanamide;

[0059]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(benzothiazol-6-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-3-methyl-butanamide;

[0060]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(benzothiazol-6-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-3S-methyl-pentanamide;

[0061]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(benzothiazol-6-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-4-pentynamide;

[0062]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(2-naphthyl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-3,3-dimethyl-butanamide;

[0063]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(2-naphthyl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-3-methyl-butanamide;

[0064]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(2-naphthyl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-3S-methyl-pentanamide;

[0065]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(2-naphthyl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-4-pentynamide;

[0066]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(1,4-benzodioxan-6-yl)sulfonyl](2-methylpropyl)amino]-S-(phenylmethyl)propyl]-3,3-dimethyl-butanamide;

[0067]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(1,4-benzodioxan-6-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-3-methyl-butanamide;

[0068]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(1,4-benzodioxan-6-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-3S-methyl-pentanamide;and

[0069]2S-[[(pyrrolidin-2-yl)carbonyl]amino]-N-[2R-hydroxy-3-[[(1,4-benzodioxan-6-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-4-pentynamide.

[0070] As utilized herein, the term “alkyl”, alone or in combination,means a straight-chain or branched-chain alkyl radical containingpreferably from 1 to 8 carbon atoms, more preferably from 1 to 5 carbonatoms, most preferably 1-3 carbon atoms. Examples of such radicalsinclude methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl,sec-butyl, tert-butyl, pentyl, iso-amyl, hexyl, octyl and the like. Theterm “alkenyl”, alone or in combination, means a straight-chain orbranched-chain hydrocarbon radical having one or more double bonds andcontaining preferably from 2 to 10 carbon atoms, more preferably from 2to 8 carbon atoms, most preferably from 2 to 5 carbon atoms. Examples ofsuitable alkenyl radicals include ethenyl, propenyl, 2-methylpropenyl,1,4-butadienyl and the like. The term “alkynyl”, alone or incombination, means a straight-chain or branched chain hydrocarbonradical having one or more triple bonds and containing preferably from 2to 10 carbon atoms, more preferably from 2 to 5 carbon atoms. Examplesof alkynyl radicals include ethynyl, propynyl (propargyl), butynyl andthe like. The term “alkoxy”, alone or in combination, means an alkylether radical wherein the term alkyl is as defined above. Examples ofsuitable alkyl ether radicals include methoxy, ethoxy, n-propoxy,isopropoxy, n-butoxy, iso-butoxy, sec-butoxy, tert-butoxy and the like.The term “cycloalkyl”, alone or in combination, means a saturated orpartially saturated monocyclic, bicyclic or tricyclic alkyl radicalwherein each cyclic moiety contains preferably from 3 to 8 carbon atomring members, more preferably from 3 to 7 carbon atom ring members, mostpreferably from 5 to 6 carbon atom ring members, and which mayoptionally be a benzo fused ring system which is optionally substitutedas defined herein with respect to the definition of aryl. Examples ofsuch cycloalkyl radicals include cyclopropyl, cyclobutyl, cyclopentyl,cyclohexyl, cycloheptyl, octahydronaphthyl, 2,3-dihydro-1H-indenyl,adamantyl and the like. “Bicyclic” and “tricyclic” as used herein areintended to include both fused ring systems, such as naphthyl andβ-carbolinyl, and substituted ring systems, such as biphenyl,phenylpyridyl, naphthyl and diphenylpiperazinyl. The term“cycloalkylalkyl” means an alkyl radical as defined above which issubstituted by a cycloalkyl radical as defined above. Examples of suchcycloalkylalkyl radicals include cyclopropylmethyl, cyclobutylmethyl,cyclopentylmethyl, cyclohexylmethyl, 1-cyclopentylethyl,1-cyclohexylethyl, 2-cyclopentylethyl, 2-cyclohexylethyl,cyclobutylpropyl, cyclopentylpropyl, cyclohexylbutyl and the like. Theterm “benzo”, alone or in combination, means the divalent radicalC₆H₄=derived from benzene. The term “aryl”, alone or in combination,means a phenyl or naphthyl radical which is optionally substituted withone or more substituents selected from alkyl, alkoxy, halogen, hydroxy,amino, nitro, cyano, haloalkyl, carboxy, alkoxycarbonyl, cycloalkyl,heterocyclo, alkanoylamino, amido, amidino, alkoxycarbonylamino,N-alkylamidino, alkylamino, dialkylamino, N-alkylamido,N,N-dialkylamido, aralkoxycarbonylamino, alkylthio, alkylsulfinyl,alkylsulfonyl and the like. Examples of aryl radicals are phenyl,p-tolyl, 4-methoxyphenyl, 4-(tert-butoxy)phenyl,3-methyl-4-methoxyphenyl, 4-fluorophenyl, 4-chlorophenyl, 3-nitrophenyl,3-aminophenyl, 3-acetamidophenyl, 4-acetamidophenyl,2-methyl-3-acetamidophenyl, 4-CF₃-phenyl, 2-methyl-3-aminophenyl,3-methyl-4-aminophenyl, 2-amino-3-methylphenyl,2,4-dimethyl-3-aminophenyl, 4-hydroxyphenyl, 3-methyl-4-hydroxyphenyl,1-naphthyl, 2-naphthyl, 3-amino-1-naphthyl, 2-methyl-3-amino-1-naphthyl,6-amino-2-naphthyl, 4,6-dimethoxy-2-naphthyl, piperazinylphenyl and thelike. The terms “aralkyl” and “aralkoxy”, alone or in combination, meansan alkyl or alkoxy radical as defined above in which at least onehydrogen atom is replaced by an aryl radical as defined above, such asbenzyl, benzyloxy, 2-phenylethyl, dibenzylmethyl, hydroxyphenylmethyl,methylphenylmethyl, diphenylmethyl, diphenylmethoxy,4-methoxyphenylmethoxy and the like. The term “aralkoxycarbonyl”, aloneor in combination, means a radical of the formula aralkyl-O—C(O)— inwhich the term “aralkyl”, has the significance given above. Examples ofan aralkoxycarbonyl radical are benzyloxycarbonyl and4-methoxyphenylmethoxycarbonyl. The term “aryloxy” means a radical ofthe formula aryl-O— in which the term aryl has the significance givenabove. The term “alkanoyl”, alone or in combination, means an acylradical derived from an alkanecarboxylic acid, examples of which includeacetyl, propionyl, butyryl, valeryl, 4-methylvaleryl, and the like. Theterm “cycloalkylcarbonyl”, means an acyl radical of the formulacycloalkyl-C(O)— in which the term “cycloalkyl” has the significancegive above, such as cyclopropylcarbonyl, cyclohexylcarbonyl,adamantylcarbonyl, 1,2,3,4-tetrahydro-2-naphthoyl,2-acetamido-1,2,3,4-tetrahydro-2-naphthoyl,1-hydroxy-1,2,3,4-tetrahydro-6-naphthoyl and the like. The term“aralkanoyl” means an acyl radical derived from an aryl-substitutedalkanecarboxylic acid such as phenylacetyl, 3-phenylpropionyl(hydrocinnamoyl), 4-phenylbutyryl, (2-naphthyl)acetyl,4-chlorohydrocinnamoyl, 4-aminohydrocinnamoyl, 4-methoxyhydrocinnamoyl,and the like. The term “aroyl” means an acyl radical derived from anarylcarboxylic acid, “aryl” having the meaning given above. Examples ofsuch aroyl radicals include substituted and unsubstituted benzoyl ornapthoyl such as benzoyl, 4-chlorobenzoyl, 4-carboxybenzoyl,4-(benzyloxycarbonyl)benzoyl, 1-naphthoyl, 2-naphthoyl, 6-carboxy-2naphthoyl, 6-(benzyloxycarbonyl)-2-naphthoyl, 3-benzyloxy-2-naphthoyl,3-hydroxy-2-naphthoyl, 3-(benzyloxyformamido)-2-naphthoyl, and the like.The term “heterocyclo,” alone or in combination, means a saturated orpartially unsaturated monocyclic, bicyclic or tricyclic heterocycleradical containing at least one, preferably 1 to 4, more preferably 1 to2, nitrogen, oxygen or sulfur atom ring members and having preferably 3to 8 ring members in each ring, more preferably 3 to 7 ring members ineach ring and most preferably 5 to 6 ring members in each ring.“Heterocyclo” is intended to include sulfones, sulfoxides, N-oxides oftertiary nitrogen ring members, and carbocyclic fused and benzo fusedring systems. Such heterocyclo radicals may be optionally substituted onat least one, preferably 1 to 4, more preferably 1 to 2, carbon atoms byhalogen, alkyl, alkoxy, hydroxy, oxo, aryl, aralkyl, heteroaryl,heteroaralkyl, amidino, N-alkylamidino, alkoxycarbonylamino,alkylsulfonylamino and the like, and/or on a secondary nitrogen atom(i.e., —NH—) by hydroxy, alkyl, aralkoxycarbonyl, alkanoyl,heteroaralkyl, phenyl or phenylalkyl, and/or on a tertiary nitrogen atom(i.e., ═N—) by oxido. “Heterocycloalkyl” means an alkyl radical asdefined above in which at least one hydrogen atom is replaced by aheterocyclo radical as defined above, such as pyrrolidinylmethyl,tetrahydrothienylmethyl, pyridylmethyl and the like. The term“heteroaryl”, alone or in combination, means an aromatic heterocycloradical as defined above, which is optionally substituted as definedabove with respect to the definitions of aryl and heterocyclo. Examplesof such heterocyclo and heteroaryl groups are pyrrolidinyl, piperidinyl,piperazinyl, morpholinyl, thiamorpholinyl, pyrrolyl, imidazolyl (e.g.,imidazol 4-yl, 1-benzyloxycarbonylimidazol-4-yl, etc.), pyrazolyl,pyridyl, (e.g., 2-(1-piperidinyl)pyridyl and 2-(4-benzylpiperazin-1-yl-1-pyridinyl, etc.), pyrazinyl, pyrimidinyl, furyl,tetrahydrofuryl, thienyl, tetrahydrothienyl and its sulfoxide andsulfone derivatives, triazolyl, oxazolyl, thiazolyl, indolyl (e.g.,2-indolyl, etc.), quinolinyl, (e.g., 2-quinolinyl, 3-quinolinyl,1-oxido-2-quinolinyl, etc.), isoquinolinyl (e.g., 1-isoquinolinyl,3-isoquinolinyl, etc.), tetrahydroquinolinyl (e.g.,1,2,3,4-tetrahydro-2-quinolyl, etc.), 1,2,3,4-tetrahydroisoquinolinyl(e.g., 1,2,3,4-tetrahydro-1-oxo-isoquinolinyl, etc.), quinoxalinyl,β-carbolinyl, 2-benzofurancarbonyl, 1-, 2-, 4- or 5-benzimidazolyl,methylenedioxyphen-4-yl, methylenedioxyphen-5-yl, ethylenedioxyphenyl,benzothiazolyl, benzopyranyl, benzofuryl, 2,3-dihydrobenzofuryl,benzoxazolyl, thiophenyl and the like. The term“cycloalkylalkoxycarbonyl” means an acyl group derived from acycloalkylalkoxycarboxylic acid of the formula cycloalkylalkyl-O—COOHwherein cycloalkylalkyl has the meaning given above. The term“aryloxyalkanoyl” means an acyl radical of the formula aryl-O-alkanoylwherein aryl and alkanoyl have the meaning given above. The term“heterocycloalkoxycarbonyl”, means an acyl group derived fromheterocycloalkyl-O—COOH wherein heterocycloalkyl is as defined above.The term “heterocycloalkanoyl” is an acyl radical derived from aheterocycloalkylcarboxylic acid wherein heterocyclo has the meaninggiven above. The term “heterocycloalkoxycarbonyl” means an acyl radicalderived from a heterocycloalkyl-O—COOH wherein heterocyclo has themeaning given above. The term “heteroaryloxycarbonyl” means an acylradical derived from a carboxylic acid represented by heteroaryl-O—COOHwherein heteroaryl has the meaning given above. The term“aminocarbonyl”, alone or in combination, means an amino-substitutedcarbonyl (carbamoyl) group wherein the amino group can be a primary,secondary or tertiary amino group containing substituents selected fromalkyl, aryl, aralkyl, cycloalkyl, cycloalkylalkyl radicals and the like.The term “aminoalkanoyl” means an acyl group derived from anamino-substituted alkylcarboxylic acid wherein the amino group can be aprimary, secondary or tertiary amino group containing substituentsselected from alkyl, aryl, aralkyl, cycloalkyl, cycloalkylalkyl radicalsand the like. The term “halogen” means fluorine, chlorine, bromine oriodine. The term “haloalkyl” means an alkyl radical having the meaningas defined above wherein one or more hydrogens are replaced with ahalogen. Examples of such haloalkyl radicals include chloromethyl,1-bromoethyl, fluoromethyl, difluoromethyl, trifluoromethyl,1,1,1-trifluoroethyl and the like. The term “leaving group” (L or W)generally refers to groups readily displaceable by a nucleophile, suchas an amine, a thiol or an alcohol nucleophile. Such leaving groups arewell known in the art. Examples of such leaving groups include, but arenot limited to, N-hydroxysuccinimide, N-hydroxybenzotriazole, halides,triflates, tosylates and the like. Preferred leaving groups areindicated herein where appropriate.

[0071] Procedures for preparing the compounds of Formula I are set forthbelow. It should be noted that the general procedure is shown as itrelates to preparation of compounds having the specifiedstereochemistry, for example, wherein the absolute stereochemistry aboutthe hydroxyl group is designated as (R). However, such procedures aregenerally applicable to those compounds of opposite configuration, e.g.,where the stereochemistry about the hydroxyl group is (S). In addition,the compounds having the (R) stereochemistry can be utilized to producethose having the (S) stereochemistry. For example, a compound having the(R) stereochemistry can be inverted to the (S) stereochemistry usingwell-known methods.

Preparation of Compounds of Formula I

[0072] The compounds of the present invention represented by Formula Iabove can be prepared utilizing the following general procedures asschematically shown in Schemes I and II.

[0073] An N-protected chloroketone derivative of an amino acid havingthe formula:

[0074] wherein P represents an amino protecting group, and R² is asdefined above, is reduced to the corresponding alcohol utilizing anappropriate reducing agent. Suitable amino protecting groups are wellknown in the art and include carbobenzoxy, t-butoxycarbonyl, and thelike. A preferred amino protecting group is carbobenzoxy. A preferredN-protected chloroketone is N-benzyloxycarbonyl-L-phenylalaninechloromethyl ketone. A preferred reducing agent is sodium borohydride.The reduction reaction is conducted at a temperature of from −10° C. toabout 25° C., preferably at about 0° C., in a suitable solvent systemsuch as, for example, tetrahydrofuran, and the like. The N-protectedchloroketones are commercially available, e.g., such as from Bachem,Inc., Torrance, Calif. Alternatively, the chloroketones can be preparedby the procedure set forth in S. J. Fittkau, J. Prakt. Chem., 315, 1037(1973), and subsequently N-protected utilizing procedures which are wellknown in the art.

[0075] The halo alcohol can be utilized directly, as described below,or, preferably, is reacted, preferably at room temperature, with asuitable base in a suitable solvent system to produce an N-protectedamino epoxide of the formula:

[0076] wherein P and R² are as defined above. Suitable solvent systemsfor preparing the amino epoxide include ethanol, methanol, isopropanol,tetrahydrofuran, dioxane, and the like including mixtures thereof.Suitable bases for producing the epoxide from the reduced chloroketoneinclude potassium hydroxide, sodium hydroxide, potassium t-butoxide, DBUand the like. A preferred base is potassium hydroxide.

[0077] Alternatively, a protected amino epoxide can be prepared, such asin co-owned and co-pending PCT Patent Application Serial No.PCT/US93/04804 (WO 93/23388) and PCT/US94/12201, and US PatentApplication Attorney Docket No. C-2860, each of which is incorporatedherein by reference in their entirety, disclose methods of preparingchiral epoxide, chiral cyanohydrin, chiral amine and other chiralintermediates useful in the preparation of retroviral proteaseinhibitors, starting with a DL-, D- or L-amino acid which is reactedwith a suitable amino-protecting group in a suitable solvent to producean amino-protected amino acid ester. For the purposes of illustration, aprotected L-amino acid with the following formula will be used toprepare the inhibitors of this invention:

[0078] wherein P³ represents carboxyl-protecting group, e.g., methyl,ethyl, benzyl, tertiary-butyl, 4-methoxyphenylmethyl and the like; R² isas defined above; and P¹ and P² independently are selected from amineprotecting groups, including but not limited to, aralkyl, substitutedaralkyl, cycloalkenylalkyl and substituted cycloalkenylalkyl, allyl,substituted allyl, acyl, alkoxycarbonyl, aralkoxycarbonyl and silyl.Examples of aralkyl include, but are not limited to benzyl,ortho-methylbenzyl, trityl and benzhydryl, which can be optionallysubstituted with halogen, alkyl of C₁-C₈, alkoxy, hydroxy, nitro,alkylene, amino, alkylamino, acylamino and acyl, or their salts, such asphosphonium and ammonium salts. Examples of aryl groups include phenyl,naphthalenyl, indanyl, anthracenyl, durenyl, 9-(9-phenylfluorenyl) andphenanthrenyl, cycloalkenylalkyl or substituted cycloalkylenylalkylradicals containing cycloalkyls of C₆-C₁₀. Suitable acyl groups includecarbobenzoxy, t-butoxycarbonyl, iso-butoxycarbonyl, benzoyl, substitutedbenzoyl, butyryl, acetyl, trifluoroacetyl, tri-chloroacetyl, phthaloyland the like. Preferably P¹ and P² are independently selected fromaralkyl and substituted aralkyl. More preferably, each of P¹ and P² isbenzyl.

[0079] Additionally, the P¹ and/or P² protecting groups can form aheterocyclic ring with the nitrogen to which they are attached, forexample, 1,2-bis(methylene)benzene, phthalimidyl, succinimidyl,maleimidyl and the like and where these heterocyclic groups can furtherinclude adjoining aryl and cycloalkyl rings. In addition, theheterocyclic groups can be mono-, di- or tri-substituted, e.g.,nitrophthalimidyl. The term silyl refers to a silicon atom optionallysubstituted by one or more alkyl, aryl and aralkyl groups.

[0080] Suitable silyl protecting groups include, but are not limited to,trimethylsilyl, triethylsilyl, tri-isopropylsilyl,tert-butyldimethylsilyl, dimethylphenylsilyl,1,2-bis(dimethylsilyl)benzene, 1,2-bis(dimethylsilyl)ethane anddiphenylmethylsilyl. Silylation of the amine functions to provide mono-or bis-disilylamine can provide derivatives of the aminoalcohol, aminoacid, amino acid esters and amino acid amide. In the case of aminoacids, amino acid esters and amino acid amides, reduction of thecarbonyl function provides the required mono- or bis-silyl aminoalcohol.Silylation of the aminoalcohol can lead to the N,N,O-tri-silylderivative. Removal of the silyl function from the silyl ether functionis readily accomplished by treatment with, for example, a metalhydroxide or ammonium flouride reagent, either as a discrete reactionstep or in situ during the preparation of the amino aldehyde reagent.Suitable silylating agents are, for example, trimethylsilyl chloride,tert-buty-dimethylsilyl chloride, phenyldimethylsilyl chlorie,diphenylmethylsilyl chloride or their combination products withimidazole or DMF. Methods for silylation of amines and removal of silylprotecting groups are well known to those skilled in the art. Methods ofpreparation of these amine derivatives from corresponding amino acids,amino acid amides or amino acid esters are also well known to thoseskilled in the art of organic chemistry including amino acid/amino acidester or aminoalcohol chemistry.

[0081] The amino-protected L-amino acid ester is then reduced, to thecorresponding alcohol. For example, the amino-protected L-amino acidester can be reduced with diisobutylaluminum hydride at −78° C. in asuitable solvent such as toluene. Preferred reducing agents includelithium aluminium hydride, lithium borohydride, sodium borohydride,borane, lithium tri-ter-butoxyaluminum hydride, borane/THF complex. Mostpreferably, the reducing agent is diisobutylaluminum hydride (DiBAL-H)in toluene. The resulting alcohol is then converted, for example, by wayof a Swern oxidation, to the corresponding aldehyde of the formula:

[0082] wherein P¹, P² and R² are as defined above. Thus, adichloromethane solution of the alcohol is added to a cooled (−75 to−68° C.) solution of oxalyl chloride in dichloromethane and DMSO indichloromethane and stirred for 35 minutes.

[0083] Acceptable oxidizing reagents include, for example, sulfurtrioxide-pyridine complex and DMSO, oxalyl chloride and DMSO, acetylchloride or anhydride and DMSO, trifluoroacetyl chloride or anhydrideand DMSO, methanesulfonyl chloride and DMSO or tetrahydrothiophene-S-oxide, toluenesulfonyl bromide and DMSO,trifluoromethanesulfonyl anhydride (triflic anhydride) and DMSO,phosphorus pentachloride and DMSO, dimethylphosphoryl chloride and DMSOand isobutyl chloroformate and DMSO. The oxidation conditions reportedby Reetz et al [Angew Chem., 99, p. 1186, (1987)], Anqew Chem. Int. Ed.Enql., 26, p. 1141, 1987) employed oxalyl chloride and DMSO at −78° C.

[0084] The preferred oxidation method described in this invention issulfur trioxide pyridine complex, triethylamine and DMSO at roomtemperature. This system provides excellent yields of the desired chiralprotected amino aldehyde usable without the need for purification i.e.,the need to purify kilograms of intermediates by chromatography iseliminated and large scale operations are made less hazardous. Reactionat room temperature also eliminated the need for the use of lowtemperature reactor which makes the process more suitable for commercialproduction.

[0085] The reaction may be carried out under an inert atmosphere such asnitrogen or argon, or normal or dry air, under atmospheric pressure orin a sealed reaction vessel under positive pressure. Preferred is anitrogen atmosphere. Alternative amine bases include, for example,tri-butyl amine, tri-isopropyl amine, N-methylpiperidine, N-methylmorpholine, azabicyclononane, diisopropylethylamine,2,2,6,6-tetramethylpiperidine, N,N-dimethylaminopyridine, or mixtures ofthese bases. Triethylamine is a preferred base. Alternatives to pureDMSO as solvent include mixtures of DMSO with non-protic or halogenatedsolvents such as tetrahydrofuran, ethyl acetate, toluene, xylene,dichloromethane, ethylene dichloride and the like. Dipolar aproticco-solvents include acetonitrile, dimethylformamide, dimethylacetamide,acetamide, tetramethyl urea and its cyclic analog, N-methylpyrrolidone,sulfolane and the like. Rather than N,N-dibenzylphenylalaninol as thealdehyde precursor, the phenylalaninol derivatives discussed above canbe used to provide the corresponding N-monosubstituted [either P¹ orP²=H] or N,N-disubstituted aldehyde.

[0086] In addition, hydride reduction of an amide or ester derivative ofthe corresponding benzyl (or other suitable protecting group) nitrogenprotected phenylalanine, substituted phenylalanine or cycloalkyl analogof phenylalanine derivative can be carried out to provide the aldehydes.Hydride transfer is an additional method of aldehyde synthesis underconditions where aldehyde condensations are avoided, cf, OppenauerOxidation.

[0087] The aldehydes of this process can also be prepared by methods ofreducing protected phenylalanine and phenylalanine analogs or theiramide or ester derivatives by, e.g., sodium amalgam with HCl in ethanolor lithium or sodium or potassium or calcium in ammonia. The reactiontemperature may be from about −20° C. to about 45° C., and preferablyfrom abut 5° C. to about 25° C. Two additional methods of obtaining thenitrogen protected aldehyde include oxidation of the correspondingalcohol with bleach in the presence of a catalytic amount of2,2,6,6-tetramethyl-1-pyridyloxy free radical. In a second method,oxidation of the alcohol to the aldehyde is accomplished by a catalyticamount of tetrapropylammonium perruthenate in the presence ofN-methylmorpholine-N-oxide.

[0088] Alternatively, an acid chloride derivative of a protectedphenylalanine or phenylalanine derivative as disclosed above can bereduced with hydrogen and a catalyst such as Pd on barium carbonate orbarium sulphate, with or without an additional catalyst moderating agentsuch as sulfur or a thiol (Rosenmund Reduction).

[0089] The aldehyde resulting from the Swern oxidation is then reactedwith a halomethyllithium reagent, which reagent is generated in situ byreacting an alkyllithium or arylithium compound with a dihalomethanerepresented by the formula X¹CH₂X² wherein X¹ and X² independentlyrepresent I, Br or Cl. For example, a solution of the aldehyde andchloroiodomethane in THF is cooled to −78° C. and a solution ofn-butyllithium in hexane is added. The resulting product is a mixture ofdiastereomers of the corresponding amino-protected epoxides of theformulas:

[0090] The diastereomers can be separated e.g., by chromatography, or,alternatively, once reacted in subsequent steps the diastereomericproducts can be separated. A D-amino acid can be utilized in place ofthe L-amino acid in order to prepare compounds having an (S)stereochemistry at the carbon bonded to R².

[0091] The addition of chloromethylithium or bromomethylithium to achiral amino aldehyde is highly diastereoselective. Preferably, thechloromethyllithium or bromomethylithium is generated in-situ from thereaction of the dihalomethane and n-butyllithium. Acceptablemethyleneating halomethanes include chloroiodomethane,bromochloromethane, dibromomethane diiodomethane, bromofluoromethane andthe like. The sulfonate ester of the addition product of, for example,hydrogen bromide to formaldehyde is also a methyleneating agent.Tetrahydrofuran is the preferred solvent, however alternative solventssuch as toluene, dimethoxyethane, ethylene dichloride, methylenechloride can be used as pure solvents or as a mixture. Dipolar aproticsolvents such as acetonitrile, DMF, N-methylpyrrolidone are useful assolvents or as part of a solvent mixture. The reaction can be carriedout under an inert atmosphere such as nitrogen or argon. For n-butyllithium can be substituted other organometalic reagents reagents such asmethyllithium, tert-butyl lithium, sec-butyl lithium, phenyllithium,phenyl sodium and the like. The reaction can be carried out attemperatures of between about −80° C. to 0° C. but preferably betweenabout −80° C. to −20° C. The most preferred reaction temperatures arebetween −40° C. to −15° C. Reagents can be added singly but multipleadditions are preferred in certain conditions. The preferred pressure ofthe reaction is atmospheric however a positive pressure is valuableunder certain conditions such as a high humidity environment.

[0092] Alternative methods of conversion to the epoxides of thisinvention include substitution of other charged methylenation precurserspecies followed by their treatment with base to form the analogousanion. Examples of these species include trimethylsulfoxonium tosylateor triflate, tetramethylammonium halide, methyldiphenylsulfoxoniumhalide wherein halide is chloride, bromide or iodide.

[0093] The conversion of the aldehydes of this invention into theirepoxide derivative can also be carried out in multiple steps. Forexample, the addition of the anion of thioanisole prepared from, forexample, a butyl or aryl lithium reagent, to the protectedaminoaldehyde, oxidation of the resulting protected aminosulfide alcoholwith well known oxidizing agents such as hydrogen peroxide, tert-butylhypochlorite, bleach or sodium periodate to give a sulfoxide. Alkylationof the sulfoxide with, for example, methyl iodide or bromide, methyltosylate, methyl mesylate, methyl triflate, ethyl bromide, isopropylbromide, benzyl chloride or the like, in the presence of an organic orinorganic base Alternatively, the protected aminosulfide alcohol can bealkylated with, for example, the alkylating agents above, to provide asulfonium salts that are subsequently converted into the subjectepoxides with tert-amine or mineral bases.

[0094] The desired epoxides formed, using most preferred conditions,diastereoselectively in ratio amounts of at least about an 85:15 ratio(S:R) The product can be purified by chromatography to give thediastereomerically and enantiomerically pure product but it is moreconveniently used directly without purification to prepare retroviralprotease inhibitors. The foregoing process is applicable to mixtures ofoptical isomers as well as resolved compounds. If a particular opticalisomer is desired, it can be selected by the choice of startingmaterial, e.g., L-phenylalanine, D-phenylalanine, L-phenylalaminol,D-phenylalaminol, D-hexahydrophenylalaminol and the like, or resolutioncan occur at intermediate or final steps. Chiral auxiliaries such as oneor two equivilants of camphor sulfonic acid, citric acid, camphoricacid, 2-methoxyphenylacetic acid and the like can be used to form salts,esters or amides of the compounds of this invention. These compounds orderivatives can be crystallized or separated chromatographically usingeither a chiral or achiral column as is well known to those skilled inthe art.

[0095] The amino epoxide is then reacted, in a suitable solvent system,with an equal amount, or preferably an excess of, a desired amine of theformula R³NH₂, wherein R³ is hydrogen or is as defined above. Thereaction can be conducted over a wide range of temperatures, e.g., fromabout 10° C. to about 100° C., but is preferably, but not necessarily,conducted at a temperature at which the solvent begins to reflux.Suitable solvent systems include protic, non-protic and dipolar aproticorganic solvents such as, for example, those wherein the solvent is analcohol, such as methanol, ethanol, isopropanol, and the like, etherssuch as tetrahydrofuran, dioxane and the like, and toluene,N,N-dimethylformamide, dimethyl sulfoxide, and mixtures thereof. Apreferred solvent is isopropanol. The resulting product is a3-(N-protected amino)-3-(R²)-1-(NHR³)-propan-2-ol derivative(hereinafter referred to as an amino alcohol) can be represented by theformulas:

[0096] wherein P, P¹, P², R² and R³ are as described above.Alternatively, a haloalcohol can be utilized in place of the aminoepoxide.

[0097] The amino alcohol defined above is then reacted in a suitablesolvent with the sulfonyl chloride R⁴SO₂Cl, the sulfonyl bromide R⁴SO₂Bror the corresponding sulfonyl anhydride, preferably in the presence ofan acid scavenger. Suitable solvents in which the reaction can beconducted include methylene chloride, tetrahydrofuran and the like.Suitable acid scavengers include triethylamine, pyridine and the like.The resulting sulfonamide derivative can be represented, depending onthe epoxide utilized by the formulas

[0098] wherein P, P¹, P², R², R³ and R⁴ are as defined above. Theseintermediates are useful for preparing inhibitor compounds of thepresent invention.

[0099] The sulfonyl halides of the formula R⁴SO₂X can be prepared by thereaction of a suitable aryl, heteroaryl and benzo fused heterocycloGrignard or lithium reagents with sulfuryl chloride, or sulfur dioxidefollowed by oxidation with a halogen, preferably chlorine. Aryl,heteroaryl and benzo fused heterocyclo Grignard or lithium reagents canbe prepared from their corresponding halide (such as chloro or bromo)compounds which are commercially available or readily prepared fromcommercially available starting materials using known methods in theart. Also, thiols may be oxidized to sulfonyl chlorides using chlorinein the presence of water under carefully controlled conditions.Additionally, sulfonic acids, such as arylsulfonic acids, may beconverted to sulfonyl halides using reagents such as PCl₅, SOCl₂,ClC(O)C(O)Cl and the like, and also to anhydrides using suitabledehydrating reagents. The sulfonic acids may in turn be prepared usingprocedures well known in the art. Some sulfonic acids are commerciallyavailable. In place of the sulfonyl halides, sulfinyl halides (R⁴SOX) orsulfenyl halides (R⁴SX) can be utilized to prepare compounds wherein the—SO₂— moiety is replaced by an —SO— or —S— moiety, respectively.Arylsulfonic acids, benzo fused heterocyclo sulfonic acids or heteroarylsulfonic acids can be prepared by sulfonation of the aromatic ring bywell known methods in the art, such as by reaction with sulfuric acid,SO₃, SO₃ complexes, such as DMF(SO₃), pyridine(SO₃),N,N-dimethylacetamide(SO₃), and the like. Preferably, arylsulfonylhalides are prepared from aromatic compounds by reaction with DMF(SO₃)and SOCl₂ or ClC(O)C(O)Cl. The reactions may be performed stepwise or ina single pot.

[0100] Arylsulfonic acids, benzo fused heterocyclo sulfonic acids,heteroaryl sulfonic acids, arylmercaptans, benzo fused heterocyclomercaptans, heteroarylmercaptans, arylhalides, benzo fused heterocyclohalides, heteroarylhalides, and the like are commercially available orcan be readily prepared from starting materials commercially availableusing standard methods well known in the art. For example, a number ofsulfonic acids (R⁴SO₃H) represented by the formulas

[0101] wherein A, B, Z, R⁶, R⁷ and R⁹ are as defined above, have beenprepared from 1,2-benzenedithiol, 2-mercaptanphenol, 1,2-benzenediol,2-aminobenzothiazole, benzothiazole, 2-aminobenzimidazole,benzimidazole, and the like, which are commercially available, byCarter, U.S. Pat. No. 4,595,407; Ehrenfreund et al., U.S. Pat. No.4,634,465; Yoder et al., J. Heterocycl. Chem. 4:166-167 (1967); Cole etal., Aust. J. Chem. 33:675-680 (1980); Cabiddu et al., Synthesis 797-798(1976); Ncube et al., Tet. Letters 2345-2348 (1978); Ncube et al., Tet.Letters 255-256 (1977); Ansink & Cerfontain, Rec. Trav. Chim.Pays-Bas108:395-403 (1989); and Kajihara & Tsuchiya, EP 638564 A1, each of whichare incorporated herein by reference in their entirety. For example,1,2-benzenedithiol, 2-mercaptanphenol or 1,2-benzenediol can be reactedwith R⁶R⁷C(L′)₂, where L′ is as defined below, preferably, Br or I, inthe presence of a base, such as hydroxide, or R⁶R⁷C═O in the presence ofacid, such as toluenesulfonic acid, or P₂O₅., to prepare the substitutedbenzo fused heterocycle of formula

[0102] which can then be sulfonylated to the sulfonic acid above. Forexample, CF₂Br₂ or CD₂Br₂ can be reacted with 1,2-benzenedithiol,2-mercaptanphenol or 1,2-benzenediol in the presence of base to producethe compounds

[0103] respectively, wherein A and B are O or S and D is a deuteriumatom. Also, when A and/or B represent S, the sulfur can be oxidizedusing the methods described below to the sulfone or sulfoxidederivatives.

[0104] Following preparation of the sulfonamide derivative, the aminoprotecting group P or P¹ and P² amino protecting groups are removedunder conditions which will not affect the remaining portion of themolecule. These methods are well known in the art and include acidhydrolysis, hydrogenolysis and the like. A preferred method involvesremoval of the protecting group, e.g., removal of a carbobenzoxy group,by hydrogenolysis utilizing palladium on carbon in a suitable solventsystem such as an alcohol, acetic acid, and the like or mixturesthereof. Where the protecting group is a t-butoxycarbonyl group, it canbe removed utilizing an inorganic or organic acid, e.g., HCl ortrifluoroacetic acid, in a suitable solvent system, e.g., dioxane ormethylene chloride. The resulting product is the amine salt derivative.

[0105] Following neutralization of the salt, the amine is then coupledto the DL-, D-, or L-amino acid corresponding to the formulaPNHCH(R¹)COOH, wherein P and R¹ are as defined above, followed bydeprotection of the amine as described above, and coupling tocyclic-amino acids of the formulas

[0106] wherein n, P, R¹⁰, R¹¹, R¹² and R¹³ are as defined above, and Lis leaving group such as halide, anhydride, active ester, and the like.For example when R¹¹, R¹² and R¹³ are each hydrogen radical, N-protectedor N-substituted proline HOBT active ester, N-protected or N-substitutedpipecolinic acid N-hydroxysuccinamide active ester, and the like can beused.

[0107] Alternatively, the intermediate

[0108] can be deprotected reacted with R¹⁰L, wherein R¹⁰ is alkyl orbenzyl, or the coresponding aldehyde or ketone followed by reduction,such as with sodium cyanoborohydride and the like, to yield

[0109] wherein n, R¹, R², R³, R⁴, R¹⁰, R¹¹, R¹² and R¹³ are as definedabove

[0110] Cyclic-amino acids of formula

[0111] are commercially available, such as proline, 4-hydroxyproline,N-methylproline, indoline-2-carboxylic acid, and the like; or canreadily be prepared from commercially available starting materials usingstandard methods well known in the art, such as proline,4-hydroxyproline, 4-hydroxyquinoline-2-carboxylic acid,3-hydroxypicolinic acid, indoline-2-carboxylic acid,5-methoxyindole-2-carboxylic acid, kainic acid,4-methoxy-2-quinolinecarboxylic acid, and the like. Alternatively, thecyclic-amino acids can be readily prepared by cyclization of aminecontaining alpha-ketone carboxylic acids or esters to a cyclic iminefollowed by reduction, such as with sodium cyanoborohydride and thelike, to the cyclic amine as shown in Scheme III, or alternatively, bycyclization of amino acids having the proper leaving group L, such aschloro, bromo, tosylate, mesylate and the like, as shown in Scheme IV,wherein n, P³, R¹⁰, R¹¹, R¹² and R¹³ are as defined above. Thealpha-ketone carboxylic acid or ester and the amino acid startingmaterials are commercialy available or readily prepared fromcommercially available materials using methods and procedures well knownin the art.

[0112] Alternatively, following neutralization of the salt, the amine isthen coupled to the DL-, D-, or L-amino acid corresponding to theformulas

[0113] wherein n, P, R¹, R¹⁰, R¹¹, R¹² and R¹³ are as defined above,which can be prepared in a similar fashion to the coupling methodsdescribed above from DL-, D-, or L-amino acid corresponding to theformula NH₂CH(R¹)COOP³, wherein P³ and R¹ are as defined above.

[0114] The DL-, D-, or L-amino acid corresponding to the formulaPNHCH(R¹)COOH or NH₂CH(R¹)COOP³, wherein P, P³ and R¹ are as definedabove, are commercially available (Sigma Chemical Co.), or readilyprepared using standard methods well known in the art from readilyavailable starting materials. Preferably, P is a benzyloxycarbonyl ort-butoxycarbonyl radical and P³ is benzyl or tert-butyl radicals.Standard coupling procedures can be used to couple the amino acids andamines. The carboxylic acid group is reacted to form an anhydride, mixedanhydride, acid halide, such as chloride or bromide, or active ester,such as esters of N-hydroxysuccinimide, HOBT and the like, using wellknown procedures and conditions. Appropriate solvent systems includetetrahydrofuran, ethylether, methyl-tert-butylether, methylene chloride,N,N-dimethylformamide and the like, including mixtures thereof.

[0115] Alternatively, the protected amino alcohol from the epoxideopening can be further protected at the newly introduced amino groupwith a protecting group P′ which is not removed with the removal of theamino protecting groups P or P¹ and P². One skilled in the art canchoose appropriate combinations of P′, P, P¹ and P². For example,suitable combinations are P=Cbz and P′=Boc; P′=Cbz and P=Boc; P¹=Cbz,P²=benzyl and P′=Boc; and P¹=P²=benzyl and P′=Boc. The resultingcompound represented by the formula

[0116] can be carried through the remainder of the synthesis to providea compound of the formulas

[0117] wherein n, P, P′, R¹, R², R³, R¹⁰, R¹¹, R¹² and R¹³ are asdefined above. The protecting group P′ is then selectively removed andthe resulting amine is reacted with the sulfonyl chloride R⁴SO₂Cl, thesulfonyl bromide R⁴SO₂Br or the corresponding sulfonyl anhydride,preferably in the presence of an acid scavenger, followed by selectiveremoval of the protecting group P when present to form the compounds ofthe present invention. This selective deprotection and conversion to thesulfonamide can be accomplished at either the end of the synthesis or atany appropriate intermediate step if desired.

[0118] The chemical reactions described above are generally disclosed interms of their broadest application to the preparation of the compoundsof this invention. Occasionally, the reactions may not be applicable asdescribed to each compound included within the disclosed scope. Thecompounds for which this occurs will be readily recognized by thoseskilled in the art. In all such cases, either the reactions can besuccessfully performed by conventional modifications known to thoseskilled in the art, e.g., by appropriate protection of interferinggroups, by changing to alternative conventional reagents, by routinemodification of reaction conditions, and the like, or other reactionsdisclosed herein or otherwise conventional, will be applicable to thepreparation of the corresponding compounds of this invention. In allpreparative methods, all starting materials are known or readilyprepared from known starting materials.

[0119] Without further elaboration, it is believed that one skilled inthe art can, using the preceding description, utilize the presentinvention to its fullest extent. The following preferred specificembodiments are, therefore, to be construed as merely illustrative, andnot limitative of the remainder of the disclosure in any way whatsoever.

[0120] All reagents were used as received without purification. Allproton and carbon NMR spectra were obtained on either a Varian VXR-300or VXR-400 nuclear magnetic resonance spectrometer.

[0121] The following Examples illustrate the preparation of inhibitorcompounds of the present invention and intermediates useful in preparingthe inhibitor compounds of the present invention.

EXAMPLE 1

[0122]

[0123] Preparation of 2S-[Bis(phenylmethyl)amino]benzenepropanol

[0124] Method 1: 2S-[Bis(phenylmethyl)amino]benzenepropanol from theDIBAL Reduction of N,N-bis(phenylmethyl)-L-Phenylalanine PhenylmethylEster

[0125] Step 1:

[0126] A solution of L-phenylalanine (50.0 g, 0.302 mol), sodiumhydroxide (24.2 g, 0.605 mol) and potassium carbonate (83.6 g, 0.605mol) in water (500 mL) was heated to 97° C. Benzyl bromide (108.5 mL,0.605 mol) was then slowly added (addition time −25 min). The mixturewas stirred at 97° C. for 30 minutes under a nitrogen atmosphere. Thesolution was cooled to room temperature and extracted with toluene(2×250 mL). The combined organic layers were washed with water andbrine, dried over magnesium sulfate, filtered and concentrated to anoil. The identity of the product was confirmed as follows. AnalyticalTLC (10% ethyl acetate/hexane, silica gel) showed major component at Rfvalue=0.32 to be the desired tribenzylated compound,N,N-bis(phenylmethyl)-L-phenylalanine phenylmethyl ester. This compoundcan be purified by column chromatography (silica gel, 15% ethylacetate/hexane). Usually the product is pure enough to be used directlyin the next step without further purification. ¹H NMR spectrum was inagreement with published literature. ¹H NMR (CDCL₃) ∂, 3.00 and 3.14(ABX-system, 2H, J_(AB)=14.1 Hz, J_(AX)=7.3 Hz and J_(BX)=5.9 Hz), 3.54and 3.92 (AB-System, 4H, J_(AB)=13.9 Hz), 3.71 (t, 1H, J=7.6 Hz), 5.11and 5.23 (AB-System, 2H, J_(AB)=12.3 Hz), and 7.18 (m, 20H). EIMS: m/z434 (M−1).

[0127] Step 2:

[0128] The benzylated phenylalanine phenylmethyl ester (0.302 mol) fromthe previous reaction was dissolved in toluene (750 mL) and cooled to−55° C. A 1.5 M solution of DIBAL in toluene (443.9 mL, 0.666 mol) wasadded at a rate to maintain the temperature between −55 to −50° C.(addition time −1 hr). The mixture was stirred for 20 minutes under anitrogen atmosphere and then quenched at −55° C. by the slow addition ofmethanol (37 ml). The cold solution was then poured into cold (5° C.)1.5 N HCl solution (1.8 L). The precipitated solid (approx. 138 g) wasfiltered off and washed with toluene. The solid material was suspendedin a mixture of toluene (400 mL) and water (100 ml). The mixture wascooled to 5° C. and treated with 2.5 N NaOH (186 mL) and then stirred atroom temperature until solid dissolved. The toluene layer was separatedfrom the aqueous phase and washed with water and brine, dried overmagnesium sulfate, filtered and concentrated to a volume of 75 mL (89g). Ethyl acetate (25 mL) and hexane (25 mL) were added to the residueupon which the desired alcohol product began to crystallize. After 30min, an additional 50 mL hexane were added to promote furthercrystallization. The solid was filtered off and washed with 50 mL hexaneto give 34.9 g of first crop product. A second crop of product (5.6 g)was isolated by refiltering the mother liquor. The two crops werecombined and recrystallized from ethyl acetate (20 mL) and hexane (30mL) to give 40 g of βS-2-[Bis(phenylmethyl)amino]benzenepropanol, 40%yield from L-phenylalanine. An additional 7 g (7%) of product can beobtained from recrystallization of the concentrated mother liquor. TLCof product Rf=0.23 (10% ethyl acetate/hexane, silica gel); ¹H NMR(CDCl₃) ∂ 2.44 (m, 1H,), 3.09 (m, 2H), 3.33 (m, 1H), 3.48 and 3.92(AB-System, 4H, J_(AB)=13.3 Hz), 3.52 (m, 1H) and 7.23 (m, 15H);[α]_(D)25+42.4 (c 1.45, CH₂Cl₂); DSC 77.67° C.; Anal. Calcd. forC₂₃H₂₅ON: C, 83.34; H, 7.60; N, 4.23. Found: C, 83.43; H, 7.59; N, 4.22.HPLC on chiral stationary phase: Cyclobond I SP column (250×4.6 mmI.D.), mobile phase: methanol/triethyl ammonium acetate buffer pH 4.2(58:42, v/v), flow-rate of 0.5 ml/min, detection with detector at 230 nmand a temperature of 0° C. Retention time: 11.25 min., retention time ofthe desired product enantiomer: 12.5 min.

[0129] Method 2: Preparation ofβS-2-[Bis(phenylmethyl)amino]benzene-propanol from the N,N-Dibenzylationof L-Phenylalaninol

[0130] L-phenylalaninol (176.6 g, 1.168 mol) was added to a stirredsolution of potassium carbonate (484.6 g, 3.506 mol) in 710 mL of water.The mixture was heated to 65° C. under a nitrogen atmosphere. A solutionof benzyl bromide (400 g, 2.339 mol) in 3A ethanol (305 mL) was added ata rate that maintained the temperature between 60-68° C. The biphasicsolution was stirred at 65° C. for 55 min and then allowed to cool to10° C. with vigorous stirring. The oily product solidified into smallgranules. The product was diluted with 2.0 L of tap water and stirredfor 5 minutes to dissolve the inorganic by products. The product wasisolated by filtration under reduced pressure and washed with wateruntil the pH is 7. The crude product obtained was air dried overnight togive a semi-dry solid (407 g) which was recrystallized from 1.1 L ofethyl acetate/heptane (1:10 by volume). The product was isolated byfiltration (at −8° C.), washed with 1.6 L of cold (−10° C.) ethylacetate/heptane (1:10 by volume) and air-dried to give 339 g (88% yield)of βS-2-[Bis(phenylmethyl)amino]benzene-propanol, Mp=71.5-73.0° C. Moreproduct can be obtained from the mother liquor if necessary. The otheranalytical characterization was identical to compound prepared asdescribed in Method 1.

EXAMPLE 2

[0131]

[0132] Preparation of 2S-[Bis(phenylmethyl)amino]benzenepropanaldehyd

[0133] Method 1:

[0134] 2S-[Bis(phenylmethyl)amino]benzene-propanol (200 g, 0.604 mol)was dissolved in triethylamine (300 mL, 2.15 mol). The mixture wascooled to 12° C. and a solution of sulfur trioxide/pyridine complex (380g, 2.39 mol) in DMSO (1.6 L) was added at a rate to maintain thetemperature between 8-17° C. (addition time −1.0 h). The solution wasstirred at ambient temperature under a nitrogen atmosphere for 1.5 hourat which time the reaction was complete by TLC analysis (33% ethylacetate/hexane, silica gel). The reaction mixture was cooled with icewater and quenched with 1.6 L of cold water (10-15° C.) over 45 minutes.The resultant solution was extracted with ethyl acetate (2.0 L), washedwith 5% citric acid (2.0 L), and brine (2.2 L), dried over MgSO₄ (280 g)and filtered. The solvent was removed on a rotary evaporator at 35-40°C. and then dried under vacuum to give 198.8 g of2S-[Bis-(phenylmethyl)amino]-benzenepropanaldehyde as a pale yellow oil(99.9%). The crude product obtained was pure enough to be used directlyin the next step without purification. The analytical data of thecompound were consistent with the published literature. [α]_(D)25=−92.9°(c 1.87, CH₂Cl₂); ¹H NMR (400 MHz, CDCl₃) ∂, 2.94 and 3.15 (ABX-System,2H, J_(AB)=13.9 Hz, J_(AX)=7.3 Hz and J_(BX)=6.2 Hz), 3.56 (t, 1H, 7.1Hz), 3.69 and 3.82 (AB-System, 4H, J_(AB)=13.7 Hz), 7.25 (m, 15 H) and9.72 (s, 1H); HRMS Calcd for (M+1) C₂₃H₂₄NO 330.450, found: 330.1836.Anal. Calcd. for C₂₃H₂₃ON: C, 83.86; H, 7.04; N, 4.25. Found: C, 83.64;H, 7.42; N, 4.19. HPLC on chiral stationary phase: (S,S) Pirkle-Whelk-O1 column (250×4.6 mm I.D.), mobile phase: hexane/isopropanol (99.5:0.5,v/v), flow-rate: 1.5 ml/min, detection with UV detector at 210 nm.Retention time of the desired S-isomer: 8.75 min., retention time of theR-enantiomer 10.62 min.

[0135] Method 2:

[0136] A solution of oxalyl chloride (8.4 ml, 0.096 mol) indichloromethane (240 ml) was cooled to −74° C. A solution of DMSO (12.0ml, 0.155 mol) in dichloromethane (50 ml) was then slowly added at arate to maintain the temperature at −74° C. (addition time ˜1.25 hr).The mixture was stirred for 5 min. followed by addition of a solution ofβS-2-[bis(phenylmethyl)amino]benzene-propanol (0.074 mol) in 100 ml ofdichloromethane (addition time −20 min., temp. −75° C. to −68° C.). Thesolution was stirred at −78° C. for 35 minutes under a nitrogenatmosphere. Triethylamine (41.2 ml, 0.295 mol) was then added over 10min. (temp. −78° to −68° C.) upon which the ammonium salt precipitated.The cold mixture was stirred for 30 min. and then water (225 ml) wasadded. The dichloromethane layer was separated from the aqueous phaseand washed with water, brine, dried over magnesium sulfate, filtered andconcentrated. The residue was diluted with ethyl acetate and hexane andthen filtered to further remove the ammonium salt. The filtrate wasconcentrated to give αS-[bis(phenylmethyl)amino]benzenepropanaldehyde.The aldehyde was carried on to the next step without purification.

[0137] Method 3:

[0138] To a mixture of 1.0 g (3.0 mmoles) ofβS-2-[bis(phenylmethyl)amino]benzenepropanol 0.531 g (4.53 mmoles) ofN-methyl morpholine, 2.27 g of molecular sieves (4A) and 9.1 mL ofacetonitrile was added 53 mg (0.15 mmoles) of tetrapropylammoniumperruthenate(TPAP). The mixture was stirred for 40 minutes at roomtemperature and concentrated under reduced pressure. The residue wassuspended in 15 mL of ethyl acetate, filtered through a pad of silicagel. The filtrate was concentrated under reduced pressure to give aproduct containing approximately 50% ofαS-2-[bis(phenylmethyl)amino]benzene propanaldehyde as a pale yellowoil.

[0139] Method 4:

[0140] To a solution of 1.0 g (3.02 mmoles) ofβS-2-[bis(phenylmethyl)amino]benzenepropanol in 9.0 mL of toluene wasadded 4.69 mg (0.03 mmoles) of 2,2,6,6-tetramethyl-1-piperidinyloxy,free radical (TEMPO), 0.32 g (3.11 mmoles) of sodium bromide, 9.0 mL ofethyl acetate and 1.5 mL of water. The mixture was cooled to 0 ²C and anaqueous solution of 2.87 mL of 5% household bleach containing 0.735 g(8.75 mmoles) of sodium bicarbonate and 8.53 mL of water was addedslowly over 25 minutes. The mixture was stirred at 0 ²C for 60 minutes.Two more additions (1.44 mL each) of bleach was added followed bystirring for 10 minutes. The two phase mixture was allowed to separate.The aqueous layer was extracted twice with 20 mL of ethyl acetate. Thecombined organic layer was washed with 4.0 mL of a solution containing25 mg of potassium iodide and water (4.0 mL), 20 mL of 10% aqueoussodium thiosulfate solution and then brine solution. The organicsolution was dried over magnesium sulfate, filtered and concentratedunder reduced pressure to give 1.34 g of crude oil containing a smallamount of the desired product aldehyde,αs-[bis(phenylmethyl)amino]benzenepropanaldehyde.

[0141] Method 5:

[0142] Following the same procedures as described in Method 1 of thisExample except 3.0 equivalents of sulfur trioxide pyridine complex wasused and αS-[bis(phenylmethyl)amino]benzenepropanaldehyde was isolatedin comparable yields.

EXAMPLE 3

[0143]

[0144] Preparation ofN,N-dibenzyl-3(S)-amino-1.2-(S)-epoxy-4-phenylbutane

[0145] Method 1:

[0146] A solution of αS-[Bis(phenylmethyl)amino]benzene-propanaldehyde(191.7 g, 0.58 mol) and chloroiodomethane (56.4 mL, 0.77 mol) intetrahydrofuran (1.8 L) was cooled to −30 to −35° C. (colder temperaturesuch as −70° C. also worked well but warmer temperatures are morereadily achieved in large scale operations) in a stainless steel reactorunder a nitrogen atmosphere. A solution of n-butyl lithium in hexane(1.6 M, 365 mL, 0.58 mol) was then added at a rate that maintained thetemperature below −25° C. After addition the mixture was stirred at −30to −35° C. for 10 minutes. More additions of reagents were carried outin the following manner: (1) additional chloroiodomethane (17 mL) wasadded, followed by n-butyl lithium (110 mL) at <−25° C. After additionthe mixture was stirred at −30 to −35° C. for 10 minutes. This wasrepeated once. (2) Additional chloroiodomethane (8.5 mL, 0.11 mol) wasadded, followed by n-butyl lithium (55 mL, 0.088 mol) at <−25° C. Afteraddition the mixture was stirred at −30 to −35° C. for 10 minutes. Thiswas repeated 5 times. (3) Additional chloroiodomethane (8.5 mL, 0.11mol) was added, followed by n-butyl lithium (37 mL, 0.059 mol) at <−25°C. After addition the mixture was stirred at −30 to −35° C. for 10minutes. This was repeated once. The external cooling was stopped andthe mixture warmed to ambient temp. over 4 to 16 hours when TLC (silicagel, 20% ethyl acetate/hexane) indicated that the reaction wascompleted. The reaction mixture was cooled to 10° C. and quenched with1452 g of 16% ammonium chloride solution (prepared by dissolving 232 gof ammonium chloride in 1220 mL of water), keeping the temperature below23° C. The mixture was stirred for 10 minutes and the organic andaqueous layers were separated. The aqueous phase was extracted withethyl acetate (2×500 mL). The ethyl acetate layer was combined with thetetrahydrofuran layer. The combined solution was dried over magnesiumsulfate (220 g), filtered and concentrated on a rotary evaporator at 65°C. The brown oil residue was dried at 70° C. in vacuo (0.8 bar) for 1 hto give 222.8 g of crude material. (The crude product weight was >100%.Due to the relative instability of the product on silica gel, the crudeproduct is usually used directly in the next step without purification).The diastereomeric ratio of the crude mixture was determined by protonNMR: (2S)/(2R): 86:14. The minor and major epoxide diastereomers werecharacterized in this mixture by tlc analysis (silica gel, 10% ethylacetate/hexane), Rf=0.29 & 0.32, respectively. An analytical sample ofeach of the diastereomers was obtained by purification on silica-gelchromatography (3% ethyl acetate/hexane) and characterized as follows:

[0147] N,N,αS-Tris(phenylmethyl)-2S-oxiranemethanamine

[0148]¹H NMR (400 MHz, CDCl₃) ∂ 2.49 and 2.51 (AB-System, 1H,J_(AB)=2.82), 2.76 and 2.77 (AB-System, 1H, J_(AB)=4.03), 2.83 (m, 2H),2.99 & 3.03 (AB-System, 1H, J_(AB)=10.1 Hz), 3.15 (m, 1H), 3.73 & 3.84(AB-System, 4H, J_(AB)=14.00), 7.21 (m, 15H); ¹³C NMR (400 MHz, CDCl₃) δ139.55, 129.45, 128.42, 128.14, 128.09, 126.84, 125.97, 60.32, 54.23,52.13, 45.99, 33.76; HRMS Calcd for C₂₄H₂₆NO (M+1) 344.477, found344.2003.

[0149] N,N,αS-Tris(phenylmethyl)-2R-oxiranemethanamine

[0150]¹H NMR (300 MHz, CDCl₃) ∂ 2.20 (m, 1H), 2.59 (m, 1H), 2.75 (m,2H), 2.97 (m, 1H), 3.14 (m, 1H), 3.85 (AB-System, 4H), 7.25 (m, 15H).HPLC on chiral stationary phase: Pirkle-Whelk-O 1 column (250×4.6 mmI.D.), mobile phase: hexane/isopropanol (99.5:0.5, v/v), flow-rate: 1.5ml/min, detection with UV detector at 210 nm. Retention time of (8):9.38 min., retention time of enantiomer of (4): 13.75 min.

[0151] Method 2:

[0152] A solution of the crude aldehyde 0.074 mol and chloroiodomethane(7.0 ml, 0.096 mol) in tetrahydrofuran (285 ml) was cooled to −78° C.,under a nitrogen atmosphere. A 1.6 M solution of n-butyl lithium inhexane (25 ml, 0.040 mol) was then added at a rate to maintain thetemperature at −75° C. (addition time −15 min.). After the firstaddition, additional chloroiodomethane (1.6 ml, 0.022 mol) was addedagain, followed by n-butyl lithium (23 ml, 0.037 mol), keeping thetemperature at −75° C. The mixture was stirred for 15 min. Each of thereagents, chloroiodomethane (0.70 ml, 0.010 mol) and n-butyl lithium (5ml, 0.008 mol) were added 4 more times over 45 min. at −75° C. Thecooling bath was then removed and the solution warmed to 22° C. over 1.5hr. The mixture was poured into 300 ml of saturated aq. ammoniumchloride solution. The tetrahydrofuran layer was separated. The aqueousphase was extracted with ethyl acetate (1×300 ml). The combined organiclayers were washed with brine, dried over magnesium sulfate, filteredand concentrated to give a brown oil (27.4 g). The product could be usedin the next step without purification. The desired diastereomer can bepurified by recrystallization at a subsequent step. The product couldalso be purified by chromatography.

[0153] Method 3:

[0154] A solution of as-[Bis(phenylmethyl)amino]benzene-propanaldehyde(178.84 g, 0.54 mol) and bromochloromethane (46 mL, 0.71 mol) intetrahydrofuran (1.8 L) was cooled to −30 to −35° C. (colder temperaturesuch as −70° C. also worked well but warmer temperatures are morereadily achieved in large scale operations) in a stainless steel reactorunder a nitrogen atmosphere. A solution of n-butyl lithium in hexane(1.6 M, 340 mL, 0.54 mol) was then added at a rate that maintained thetemperature below −25° C. After addition the mixture was stirred at −30to −35° C. for 10 minutes. More additions of reagents were carried outin the following manner: (1) additional bromochloromethane (14 mL) wasadded, followed by n-butyl lithium (102 mL) at <−25° C. After additionthe mixture was stirred at −30 to −35° C. for 10 minutes. This wasrepeated once. (2) Additional bromochloromethane (7 mL, 0.11 mol) wasadded, followed by n-butyl lithium (51 mL, 0.082 mol) at <−25° C. Afteraddition the mixture was stirred at −30 to −35° C. for 10 minutes Thiswas repeated 5 times. (3) Additional bromochloromethane (7 mL, 0.11 mol)was added, followed by n-butyl lithium (51 mL, 0.082 mol) at <−25° C.After addition the mixture was stirred at −30 to −35° C. for 10 minutes.This was repeated once. The external cooling was stopped and the mixturewarmed to ambient temp. over 4 to 16 hours when TLC (silica gel, 20%ethyl acetate/hexane) indicated that the reaction was completed. Thereaction mixture was cooled to 10° C. and quenched with 1452 g of 16%ammonium chloride solution (prepared by dissolving 232 g of ammoniumchloride in 1220 mL of water), keeping the temperature below 23° C. Themixture was stirred for 10 minutes and the organic and aqueous layerswere separated. The aqueous phase was extracted with ethyl acetate(2×500 mL). The ethyl acetate layer was combined with thetetrahydrofuran layer. The combined solution was dried over magnesiumsulfate (220 g), filtered and concentrated on a rotary evaporator at 65°C. The brown oil residue was dried at 70° C. in vacuo (0.8 bar) for 1 hto give 222.8 g of crude material.

[0155] Method 4:

[0156] Following the same procedures as described in Method 3 of thisExample except the reaction temperatures were at −20° C. The resultingN,N,αS-tris(phenylmethyl)-2S-oxiranemethanamine was a diastereomericmixture of lesser purity then that of Method 3.

[0157] Method 5:

[0158] Following the same procedures as described in Method 3 of thisExample except the reaction temperatures were at −70-−78° C. Theresulting N,N,αS-tris(phenylmethyl)-2S-oxiranemethanamine was adiastereomeric mixture, which was used directly in the subsequent stepswithout purification.

[0159] Method 6:

[0160] Following the same procedures as described in Method 3 of thisExample except a continuous addition of bromochloromethane and n-butyllithium was used at −30 to −35° C. After the reaction and work upprocedures as described in Method 3 of this Example, the desiredN,N,αS-tris(phenylmethyl)-2S-oxiranemethanamine was isolated incomparable yields and purities.

[0161] Method 7:

[0162] Following the same procedures as described in Method 2 of thisExample except dibromomethane was used instead of chloroiodomethane.After the reaction and work up procedures as described in Method 2 ofthis Example, the desiredN,N,αS-tris(phenylmethyl)-2S-oxirane-methanamine was isolated.

EXAMPLE 4

[0163]

[0164] Preparation ofN-[3(S)-[N,N-bis(phenylmethyl)amino]-2(R)-hydroxy-4-phenylbutyl]-N-isobutylamine

[0165] To a solution of crudeN,N-dibenzyl-3(S)-amino-1,2(S)-epoxy-4-phenylbutane (388.5 g, 1.13 mol)in isopropanol (2.7 L) (or ethyl acetate) was added isobutylamine (1.7kgm, 23.1 mol) over 2 min. The temperature increased from 25° C. and to30° C. The solution was heated to 82° C. and stirred at this temperaturefor 1.5 hours. The warm solution was concentrated under reduced pressureat 65° C., The brown oil residue was transferred to a 3-L flask anddried in vacuo (0.8 mm Hg) for 16 h to give 450 g of3S-[N,N-bis(phenylmethyl)amino-4-phenylbutan-2R-ol as a crude oil.

[0166] An analytical sample of the desired major diastereomeric productwas obtained by purifying a small sample of crude product by silica gelchromatography (40% ethyl acetate/hexane). Tlc analysis: silica gel, 40%ethyl acetate/hexane; Rf=0.28; HPLC analysis: ultrasphere ODS column,25% triethylamino-/phosphate buffer pH 3-acetonitrile, flow rate 1mL/min, UV detector; retention time 7.49 min.; HRMS Calcd for C₂₈H₂₇N 20(M+1) 417.616, found 417.2887. An analytical sample of the minordiastereomeric product,3S-[N,N-bis(phenylmethyl)amino]1-(2-methylpropyl)amino-4-phenylbutan-2S-olwas also obtained by purifying a small sample of crude product by silicagel chromatography (40% ethyl acetate/hexane).

EXAMPLE 5

[0167]

[0168] Preparation ofN-[3(S)-[N,N-bis(phenylmethyl)amino]-2(R)-hydroxy-4-phenylbutyl]-N-isobutylamine.oxalicAcid Salt

[0169] To a solution of oxalic acid (8.08 g, 89.72 mmol) in methanol (76mL) was added a solution of crude3(S)-[N,N-bis(phenylmethyl)amino]-1-(2-methylpropyl)amino-4-phenylbutan-2(R)-ol{39.68 g, which contains about 25.44 g (61.06 mmol) of 3(S),2(R) isomerand about 4.49 g (10.78 mmol) of 3(S),2(S) isomer} in ethyl acetate (90mL) over 15 minutes. The mixture was stirred at room temperature forabout 2 hours. Solid was isolated by filtration, washed with ethylacetate (2×20 mL) and dried in vacuo for about 1 hour to yield 21.86 g(70.7% isomer recovery) of 97% diastereomerically pure salt (based onHPLC peak areas). HPLC analysis: Vydec-peptide/protein C18 column, UVdetector 254 nm, flow rate 2 mL/min., gradient {A=0.05% trifluoroaceticacid in water, B=0.05% trifluoroacetic acid in acetonitrile, 0 min. 75%A/25% B, 30 min. 10% A/90% B, 35 min. 10% A/90% B, 37 min. 75% A/25% B);Retention time 10.68 min. (3(S),2(R) isomer) and 9.73 min. (3(S),2(S)isomer). Mp=174.99° C.; Microanalysis: Calc.: C, 71.05%, H, 7.50%, N,5.53%; Found: C, 71.71%, H, 7.75%, N, 5.39%.

[0170] Alternatively, oxalic acid dihydrate (119 g, 0.94 mole) was addedto a 5000 mL round bottom flask fitted with a mechanical stirrer and adropping funnel.

[0171] Methanol (1000 ml) was added and the mixture stirred untildissolution was complete. A solution of crude3(S)-[N,N-bis(phenylmethyl)amino]-1-(2-methylpropyl)amino-4-phenylbutan-2(R)-ol in ethyl acetate (1800 ml, 0.212 g aminoalcohol isomers/mL, 0.9160 moles) was added over a twenty minute period.The mixture was stirred for 18 hours and the solid product was isolatedby centrifugation in six portions at 400 G. Each portion was washed with125 mL of ethyl acetate. The salt was then collected and dried overnightat 1 torr to yield 336.3 g of product (71% based upon total aminoalcohol). HPLC/MS (electrospray) was consistent with the desired product(m/z 417 [M+H]⁺)

[0172] Alternatively, crude 3(S)-[N,N-bis(phenylmethyl)amino]-1-(2-methylpropyl)amino-4-phenylbutan-2(R)-ol (5 g) was dissolvedin methyl-tert-butylether (MTBE) (10 mL) and oxalic acid (1 g) inmethanol (4 mL) was added. The mixture was stirred for about 2 hours.The resulting solid was filtered, washed with cold MTBE and dried toyield 2.1 g of white solid of about 98.9% diastereomerically pure (basedon HPLC peak areas).

EXAMPLE 6

[0173] Preparation ofN-[3(S)-[N,N-bis(phenylmethyl)amino]-2(R)-hydroxy-4-phenylbutyl]-N-isobutylamine.aceticAcid Salt

[0174] To a solution of crude 3(S)-[N,N-bis(phenylmethyl)amino]-1-(2-methylpropyl)amino-4-phenylbutan-2(R)-ol inmethyl-tert-butylether (MTBE) (45 mL, 1.1 g amino alcohol isomers/mL)was added acetic acid (6.9 mL) dropwise. The mixture was stirred forabout 1 hour at room temperature. The solvent was removed in vacuo toyield a brown oil about 85% diastereomerically pure product (based onHPLC peak areas). The brown oil was crystallized as follows: 0.2 g ofthe oil was dissolved in the first solvent with heat to obtain a clearsolution, the second solvent was added until the solution became cloudy,the mixture was heated again to clarity, seeded with about 99%diastereomerically pure product, cooled to room temperature and thenstored in a refrigerator overnight. The crystals were filtered, washedwith the second solvent and dried. The diastereomeric purity of thecrystals was calculated from the HPLC peak areas. The results are shownin Table 1. TABLE 1 First Second Solvent Recovery Diastereomeric SolventSolvent Ratio Weight (g) Purity (%) MTBE Heptane 1:10 0.13 98.3 MTBEHexane 1:10 0.03 99.6 Methanol Water 1:1.5 0.05 99.5 Toluene Heptane1:10 0.14 98.7 Toluene Hexane 1:10 0.10 99.7

[0175] Alternatively, crude 3(S)-[N,N-bis(phenylmethyl)amino)-1-(2-methylpropyl)amino-4-phenylbutan-2(R)-ol (50.0 g, whichcontains about 30.06 g (76.95 mmol) of 3(S),2(R) isomer and about 5.66 g(13.58 mmol) of 3(S),2(S) isomer) was dissolved inmethyl-tert-butylether (45.0 mL). To this solution was added acetic acid(6.90 mL, 120.6 mmol) over a period of about 10 min. The mixture wasstirred at room temperature for about 1 hour and concentrated underreduced pressure. The oily residue was purified by recrystallizationfrom methyl-tert-butylether (32 mL) and heptane (320 mL). Solid wasisolated by filtration, washed with cold heptane and dried in vacuo forabout 1 hour to afford 21.34 g (58.2% isomer recovery) of 96%diastereomerically pure monoacetic acid salt (based on HPLC peak areas).Mp=105-106° C.; Microanalysis: Calc.: C, 75.53%, H, 8.39%, N, 5.87%;Found: C, 75.05%, H, 8.75%, N, 5.71%.

EXAMPLE 7

[0176] Preparation ofN-[3(S)-[N,N-bis(phenylmethyl)amino]-2(R)-hydroxy-4-phenylbutyl]-N-isobutylamine-L-tartaricAcid Salt

[0177] Crude3(S)-[N,N-bis(phenylmethyl)amino]-1-(2-methylpropyl)amino-4-phenylbutan-2(R)-ol(10.48 g, which contains about 6.72 g (16.13 mmol) of 3(S),2(R) isomerand about 1.19 g (2.85 mmol) of 3(S),2(S) isomer) was dissolved intetrahydrofuran (10.0 mL). To this solution was added a solution ofL-tartaric acid (2.85 g, 19 mmol) in methanol (5.0 mL) over a period ofabout 5 min. The mixture was stirred at room temperature for about 10min. and concentrated under reduced pressure. Methyl-tert-butylether(20.0 mL) was added to the oily residue and the mixture was stirred atroom temperature for about 1 hour. Solid was isolated by filtration toafford 7.50 g of crude salt. The crude salt was purified byrecrystallization from ethyl acetate and heptane at room temperature toyield 4.13 g (45.2% isomer recovery) of 95% diastereomerically pureL-tartaric acid salt (based on HPLC peak areas). Microanalysis: Calc.: C67.76%, H 7.41%, N 4.94%; Found: C 70.06%, H 7.47%, N 5.07%.

EXAMPLE 8

[0178] Preparation ofN-[3(S)-[N,N-bis(phenylmethyl)amino]-2(R)-hydroxy-4-phenylbutyl]-N-isobutylamine.dihydrochloricAcid Salt

[0179] Crude 3(S)-[N,N-bis(phenylmethyl)amino]-1-(2-methylpropyl)amino-4-phenylbutan-2(R)-ol (10.0 g, whichcontains about 6.41 g (15.39 mmol) of 3(S),2(R) isomer and about 1.13 g(2.72 mmol) of 3(S),2(S) isomer) was dissolved in tetrahydrofuran (20.0mL). To this solution was added hydrochloric acid (20 mL, 6.0 N) over aperiod of about 5 min. The mixture was stirred at room temperature forabout 1 hour and concentrated under reduced pressure. The residue wasrecrystallized from ethanol at 0° C. to yield 3.20 g (42.7% isomerrecovery) of 98% diastereomerically pure dihydrochloric acid salt (basedon HPLC peak areas). Microanalysis: Calc.: C, 68.64%, H, 7.76%, N,5.72%; Found: C, 68.79%, H, 8.07%, N, 5.55%.

EXAMPLE 9

[0180] Preparation ofN-[3(S)-[N,N-bis(phenylmethyl)amino]-2(R)-hydroxy-4-phenylbutyl]-N-isobutylamine.toluenesulfonicAcid Salt

[0181] Crude 3(S)-[N,N-bis(phenylmethyl)amino]-1-(2-methylpropyl)amino-4-phenylbutan-2(R)-ol (5.0 g, whichcontains about 3.18 g (7.63 mmol) of 3(S),2(R) isomer and about 0.56 g(1.35 mmol) of 3(S),2(S) isomer) was dissolved in methyl-tert-butylether(10.0 ML). To this solution was added a solution of toluenesulfonic acid(2.28 g, 12 mmol) in methyl-tert-butylether (2.0 mL) and methanol (2.0mL) over a period of about 5 min. The mixture was stirred at roomtemperature for about 2 hours and concentrated under reduced pressure.The residue was recrystallized from methyl-tert-butylether and heptaneat 0° C., filtered, washed with cold heptane and dried in vacuo to yield1.85 g (40.0% isomer recovery) of 97% diastereomerically puremonotoluenesulfonic acid salt (based on HPLC peak areas).

EXAMPLE 10

[0182] Preparation ofN-[3(S)-[N,N-bis(phenylmethyl)amino]-2(R)-hydroxy-4-phenylbutyl]-N-isobutylamine.methanesulfonicAcid Salt

[0183] Crude 3(S)-[N,N-bis(phenylmethyl)amino]-1-(2-methylpropyl)amino-4-phenylbutan-2(R)-ol (10.68 g, whichcontains about 6.85 g (16.44 mmol) of 3(S),2(R) isomer and about 1.21 g(2.90 mmol) of 3(S),2(S) isomer) was dissolved in tetrahydrofuran (10.0mL). To this solution was added methanesulfonic acid (1.25 mL, 19.26mmol). The mixture was stirred at room temperature for about 2 hours andconcentrated under reduced pressure. The oily residue was recrystallizedfrom methanol and water at 0° C., filtered, washed with coldmethanol/water (1:4) and dried in vacuo to yield 2.40 g (28.5% isomerrecovery) of 98% diastereomerically pure monomethanesulfonic acid salt(based on HPLC peak areas).

EXAMPLE 11

[0184] Preparation of N-benzyl-L-phenylalaninol

[0185] Method 1:

[0186] L-Phenylalaninol (89.51 g, 0.592 moles) was dissolved in 375 mLof methanol under inert atmosphere, 35.52 g (0.592 moles) of glacialacetic acid and 50 mL of methanol was added followed by a solution of62.83 g (0.592 moles) of benzaldehyde in 100 mL of methanol. The mixturewas cooled to approximately 15° C. and a solution of 134.6 g (2.14moles) of sodium cyanoborohydride in 700 mL of methanol was added inapproximately 40 minutes, keeping the temperature between 15° C. and 25°C. The mixture was stirred at room temperature for 18 hours. The mixturewas concentrated under reduced pressure and partitioned between 1 L of2M ammonium hydroxide solution and 2 L of ether. The ether layer waswashed with 1 L of 1M ammonium hydroxide solution, twice with 500 mLwater, 500 mL of brine and dried over magnesium sulfate for 1 hour. Theether layer was filtered, concentrated under reduced pressure and thecrude solid product was recrystallized from 110 mL of ethyl acetate and1.3 L of hexane to give 115 g (81% yield) of N-benzyl-L-phenylalaninolas a white solid.

[0187] Method 2:

[0188] L-Phenylalaninol (5 g, 33 mmoles) and 3.59 g (33.83 mmoles) ofbenzaldehyde were dissolved in 55 mL of 3A ethanol under inertatmosphere in a Parr shaker and the mixture was warmed to 60° C. for 2.7hours. The mixture was cooled to approximately 25° C. and 0.99 g of 5%platinum on carbon was added and the mixture was hydrogenated at 60 psiof hydrogen and 40° C. for 10 hours. The catalyst was filtered off, theproduct was concentrated under reduced pressure and the crude solidproduct was recrystallized from 150 mL of heptane to give 3.83 g (48%yield) of N-benzyl-L-phenylalaninol as a white solid.

EXAMPLE 12

[0189] Preparation of N-(t-Butoxycarbonyl)-N-benzyl-L-phenylalaninol

[0190] N-benzyl-L-phenylalaninol (2.9 g, 12 mmoles) was dissolved in 3mL of triethylamine and 27 mL of methanol and 5.25 g (24.1 mmoles) ofdi-tert-butyl dicarbonate was added. The mixture was warmed to 60° C.for 35 minutes and concentrated under reduced pressure. The residue wasdissolved in 150 mL of ethyl acetate and washed twice with 10 mL of cold(0-5° C.), dilute hydrochloric acid (pH 2.5 to 3), 15 mL of water, 10 mLof brine, dried over magnesium sulfate, filtered and concentrated underreduced pressure. The crude product oil was purified by silica gelchromatography (ethyl acetate:hexane, 12:3 as eluting solvent) to give3.98 g (97% yield) of colorless oil.

EXAMPLE 13

[0191] Preparation of N-(t-Butoxycarbonyl)-N-benzyl-L-phenylalaninal

[0192] Method 1:

[0193] To a solution of 0.32 g (0.94 mmoles) ofN-(t-butoxycarbonyl)-N-benzyl-L-phenylalaninol in 2.8 mL of toluene wasadded 2.4 mg (0.015 mmoles) of 2,2,6,6-tetramethyl-1-piperidinyloxy,free radical (TEMPO), 0.1 g (0.97 mmoles) of sodium bromide, 2.8 mL ofethyl acetate and 0.34 mL of water. The mixture was cooled to 0° C. andan aqueous solution of 4.2 mL of 5% household bleach containing 0.23 g(3.0 mL, 2.738 mmoles) of sodium bicarbonate was added slowly over 30minutes. The mixture was stirred at 0° C. for 10 minutes. Three moreadditions (0.4 mL each) of bleach was added followed by stirring for 10minutes after each addition to consume all the stating material. The twophase mixture was allowed to separate. The aqueous layer was extractedtwice with 8 mL of toluene. The combined organic layer was washed with1.25 mL of a solution containing 0.075 g of potassium iodide, sodiumbisulfate (0.125 g) and water (1.1 mL), 1.25 mL of 10% aqueous sodiumthiosulfate solution, 1.25 mL of pH 7 phosphate buffer and 1.5 mL ofbrine solution. The organic solution was dried over magnesium sulfate,filtered and concentrated under reduced pressure to give 0.32 g (100%yield) of N-(t-Butoxycarbonyl)-N-benzyl-L-phenylalaninal.

[0194] Method 2:

[0195] To a solution of 2.38 g (6.98 mmoles) ofN-(t-butoxycarbonyl)-N-benzyl-L-phenylalaninol in 3.8 mL (27.2 mmoles)of triethylamine at 10° C. was added a solution of 4.33 g (27.2 mmoles)of sulfur trioxide pyridine complex in 17 mL of dimethyl sulfoxide. Themixture was warmed to room temperature and stirred for one hour. Water(16 mL) was added and the mixture was extracted with 20 mL of ethylacetate. The organic layer was washed with 20 mL of 5% citric acid, 20mL of water, 20 mL of brine, dried over magnesium sulfate and filtered.The filtrate was concentrated under reduced pressure to give 2.37 g(100% yield) of N-(t-Butoxycarbonyl)-N-benzyl-L-phenylalaninal.

EXAMPLE 14

[0196]

[0197] Preparation of3(S)-[N-(t-butoxycarbonyl)-N-benzylamino]-1,2-(S)-epoxy-4-phenylbutane

[0198] Method 1:

[0199] A solution of 2.5 g (7.37 mmoles) ofN-(t-butoxycarbonyl)-N-benzyl-L-phenylalaninal and 0.72 mL ofchloroiodomethane in 35 mL of THF was cooled to −78° C. A 4.64 mL of asolution of n-butyllithium (1.6 M in hexane, 7.42 mmoles) was addedslowly, keeping the temperature below −70° C. The mixture was stirredfor 10 minutes between −70 to −75° C. Two additional portions of 0.22 mLof chloroiodomethane and 1.4 mL of n-butyllithium was added sequentiallyand the mixture was stirred for 10 minutes between −70 to −75° C. aftereach addition. Four additional portions of 0.11 mL of chloroiodomethaneand 0.7 mL of n-butyllithium was added sequentially and the mixture wasstirred for 10 minutes between −70 to −75° C. after each addition. Themixture was warmed to room temperature for 3.5 hours. The product wasquenched at below 5° C. with 24 mL of ice-cold water. The biphasiclayers were separated and the aqueous layer was extracted twice with 30mL of ethyl acetate. The combined organic layers was washed three timeswith 10 mL water, then with 10 mL brine, dried over sodium sulfate,filtered and concentrated under reduced pressure to give 2.8 g of ayellow crude oil. This crude oil (>100% yield) is a mixture of thediastereomeric epoxidesN,αS-bis(phenylmethyl)-N-(t-butoxycarbonyl)-2S-oxiranemethanamine andN,αS-bis(phenylmethyl)-N-(t-butoxycarbonyl)-2R-oxiranemethanamine. Thecrude mixture is used directly in the next step without purification.

[0200] Method 2:

[0201] To a suspension of 2.92 g (13.28 mmoles) of trimethylsulfoxoniumiodide in 45 mL of acetonitrile was added 1.49 g (13.28 mmoles) ofpotassium t-butoxide. A solution of 3.0 g (8.85 mmoles) ofN-(t-butoxycarbonyl)-N-benzyl-L-phenylalaninal in 18 mL of acetonitrilewas added and the mixture was stirred at room temperature for one hour.The mixture was diluted with 150 mL of water and extracted twice with200 mL of ethyl acetate. The organic layers were combined and washedwith 100 mL water, 50 mL brine, dried over sodium sulfate, filtered andconcentrated under reduced pressure to give 3.0 g of a yellow crude oil.The crude product was purified by silica gel chromatography (ethylacetate/hexane: 1:8 as eluting solvent) to give 1.02 g (32.7% yield) ofa mixture of the two diastereomersN,αS-bis(phenylmethyl)-N-(t-butoxycarbonyl)-2S-oxiranemethanamine andN,αS-bis(phenylmethyl)-N-(t-butoxycarbonyl)-2R-oxiranemethanamine.

[0202] Method 3:

[0203] To a suspension of 0.90 g (4.42 mmoles) of trimethylsulfoniumiodide in 18 mL of acetonitrile was added 0.495 g (4.42 mmoles) ofpotassium t-butoxide. A solution of 1.0 g (2.95 mmoles) ofN-(t-butoxycarbonyl)-N-benzyl-L-phenylalaninal in 7 mL of acetonitrilewas added and the mixture was stirred at room temperature for one hour.The mixture was diluted with 80 mL of water and extracted twice with 80mL of ethyl acetate. The organic layers were combined and washed with100 mL water, 30 mL brine, dried over sodium sulfate, filtered andconcentrated under reduced pressure to give 1.04 g of a yellow crudeoil. The crude product was a mixture of the two diastereomersN,αS-bis(phenylmethyl)-N-(t-butoxycarbonyl)-2S-oxiranemethanamine andN,αS-bis(phenylmethyl)-N-(t-butoxycarbonyl)-2R-oxiranemethanamine.

EXAMPLE 15

[0204]

[0205] Preparation of3S-[N-(t-Butoxycarbonyl)-N-(phenylmethyl)amino]-1-(2-methylpropyl)amino-4-phenylbutan-2R-ol

[0206] To a solution of 500 mg (1.42 mmoles) of the crude epoxide (amixture of the two diastereomersN,αS-bis(phenylmethyl)-N-(t-butoxycarbonyl)-2S-oxiranemethanamine andN,αS-bis(phenylmethyl)-N-(t-butoxycarbonyl)-2R-oxiranemethanamine) in0.98 mL of isopropanol was added 0.71 mL (7.14 mmoles) of isobutylamine.The mixture was warmed to reflux at 85° C. to 90° C. for 1.5 hours. Themixture was concentrated under reduced pressure and the product oil waspurified by silica gel chromatography (chloroform:methanol, 100:6 aseluting solvents) to give 330 mg of3S-[N-(t-butoxycarbonyl)-N-(phenylmethyl)amino]-1-(2-methylpropyl)amino-4-phenylbutan-2R-olas a colorless oil (54.5% yield)3S-[N-(t-Butoxycarbonyl)-N-(phenylmethyl)amino]-1-(2-methylpropyl)amino-4-phenylbutan-2S-olwas also isolated. When purifiedN,αS-bis(phenylmethyl)-N-(t-butoxycarbonyl)-2S-oxiranemethanamine wasused as starting material,3S-[N-(t-butoxycarbonyl)-N-(phenylmethyl)amino]-1]-1-(2-methylpropyl)amino-4-phenylbutan-2R-olwas isolated after purification by chromatography in an 86% yield.

EXAMPLE 16

[0207]

[0208] Preparation of3S-(N-t-Butoxycarbonyl)amino-4-phenylbutan-1,2R-diol

[0209] To a solution of 1 g (3.39 mmoles) of2S-(N-t-butoxycarbonyl)amino-1S-hydroxy-3-phenylbutanoic acid(commercially available from Nippon Kayaku, Japan) in 50 mL of THF at 0°C. was added 50 mL of borane-THF complex (liquid, 1.0 M in THF), keepingthe temperatures below 5° C. The reaction mixture was warmed to roomtemperature and stirred for 16 hours. The mixture was cooled to 0° C.and 20 mL of water was added slowly to destroy the excess BH₃ and toquench the product mixture, keeping the temperature below 12° C. Thequenched mixture was stirred for 20 minutes and concentrated underreduced pressure. The product mixture was extracted three times with 60mL of ethyl acetate. The organic layers were combined and washed with 20mL of water, 25 mL of saturated sodium chloride solution andconcentrated under reduced pressure to give 1.1 g of crude oil. Thecrude product was purified by silica gel chromatography(chloroform/methanol, 10:6 as eluting solvents) to give 900 mg (94.4%yield) of 3S-(N-t-butoxycarbonyl)amino-4-phenylbutan-1,2R-diol as awhite solid.

EXAMPLE 17

[0210]

[0211] Preparation of3S-(N-t-Butoxycarbonyl)amino-2R-hydroxy-4-phenylbut-1-ylToluenesulfonate

[0212] To a solution of 744.8 mg (2.65 mmoles) of3S-(N-t-butoxycarbonyl)amino-4-phenylbutan-1,2R-diol in 13 mL ofpyridine at 0° C. ²C was added 914 mg of toluenesulfonyl chloride in oneportion. The mixture was stirred at 0° C. to 5° C. for 5 hours A mixtureof 6.5 mL of ethyl acetate and 15 mL of 5% aqueous sodium bicarbonatesolution was added to the reaction mixture and stirred for 5 minutes.The product mixture was extracted three times with 50 mL of ethylacetate. The organic layers were combined and washed with 15 mL ofwater, 10 mL of saturated sodium chloride solution and concentratedunder reduced pressure to give about 1.1 g of a yellow chunky solid. Thecrude product was purified by silica gel chromatography (ethylacetate/hexane 1:3 as eluting solvents) to give 850 mg (74% yield) of3S-(N-t-butoxycarbonyl)amino-2R-hydroxy-4-phenylbut-1-yltoluenesulfonate as a white solid.

EXAMPLE 18

[0213]

[0214] Preparation of3S-[N-(t-Butoxycarbonyl)amino]-1-(2-methylpropyl)amino-4-phenylbutan-2R-ol

[0215] To a solution of 90 mg (0.207 mmoles) of3S-(N-t-butoxycarbonyl)amino-2R-hydroxy-4-phenylbut-1-yltoluenesulfonate in 0.143 mL of isopropanol and 0.5 mL of toluene wasadded 0.103 mL (1.034 mmoles) of isobutylamine. The mixture was warmedto 80 to 85° C. and stirred for 1.5 hours. The product mixture wasconcentrated under reduced pressure at 40 to 50° C. and purified bysilica gel chromatography (chloroform/methanol, 10:1 as elutingsolvents) to give 54.9 mg (76.8% yield) of3S-[N-(t-butoxycarbonyl)amino]-1-(2-methylpropyl)amino-4-phenylbutan-2R-olas a white solid.

EXAMPLE 19

[0216]

[0217] Preparation of N-[3(S)-benzyloxycarbonylamino-2(R)-hydroxy-4-phenylbutyl]-N-isoamylamine

[0218] Part A:

[0219] To a solution of 75.0 g (0.226 mol) ofN-benzyloxycarbonyl-L-phenylalanine chloromethyl ketone in a mixture of807 mL of methanol and 807 mL of tetrahydrofuran at −2° C., was added13.17 g (0.348 mol, 1.54 equiv.) of solid sodium borohydride over onehundred minutes. The solvents were removed under reduced pressure at 40°C. and the residue dissolved in ethyl acetate (approx. 1 L). Thesolution was washed sequentially with 1M potassium hydrogen sulfate,saturated sodium bicarbonate and then saturated sodium chloridesolutions. After drying over anhydrous magnesium sulfate and filtering,the solution was removed under reduced pressure. To the resulting oilwas added hexane (approx. 1 L) and the mixture warmed to 60° C. withswirling. After cooling to room temperature, the solids were collectedand washed with 2 L of hexane. The resulting solid was recrystallizedfrom hot ethyl acetate and hexane to afford 32.3 g (43% yield) ofN-benzyloxycarbonyl-3(S)-amino-1-chloro-4-phenyl-2(S)-butanol, mp150-151° C. and M+Li⁺=340.

[0220] Part B:

[0221] To a solution of 6.52 g (0.116 mol, 1.2 equiv.) of potassiumhydroxide in 968 mL of absolute ethanol at room temperature, was added32.3 g (0.097 mol) of N-CBZ-3(S)-amino-1-chloro-4-phenyl-2(S)-butanol.After stirring for fifteen minutes, the solvent was removed underreduced pressure and the solids dissolved in methylene chloride. Afterwashing with water, drying over magnesium sulfate, filtering andstripping, one obtains 27.9 g of a white solid. Recrystallization fromhot ethyl acetate and hexane afforded 22.3 g (77% yield) ofN-benzyloxycarbonyl-3(S)-amino-1,2(S)-epoxy-4-phenylbutane, mp 102-103°C. and MH⁺ 298.

[0222] Part C:

[0223] A solution of N-benzyloxycarbonyl3(S)-amino-1,2-(S)-epoxy-4-phenylbutane (1.00 g, 3.36 mmol) andisoamylamine (4.90 g, 67.2 mmol, 20 equiv.) in 10 mL of isopropylalcohol was heated to reflux for 1.5 hours. The solution was cooled toroom temperature, concentrated in vacuo and then poured into 100 mL ofstirring hexane whereupon the product crystallized from solution. Theproduct was isolated by filtration and air dried to give 1.18 g, 95% ofN=[[3(S)-phenylmethylcarbamoyl)amino-2(R)-hydroxy-4-phenylbutyl]N-[(3-methylbutyl)]aminemp 108.0-109.5° C., MH⁺ m/z=371.

EXAMPLE 20

[0224]

[0225] Preparation ofphenylmethyl[2R-hydroxy-3-[(3-methylbutyl)(phenylsulfonyl)amino]-1S-(phenylmethyl)propyl]carbamate

[0226] From the reaction ofN[3(S)-benzyloxycarbonylamino-2(R)-hydroxy-4-phenylbutyl]N-isoamylamine(1.47 gm, 3.8 mmol), triethylamine (528 uL, 3.8 mmol) andbenzenesulfonyl chloride (483 uL, 3.8 mmol) one obtains phenylmethyl[2R-hydroxy-3-[(3-methylbutyl)(phenylsulfonyl)amino]-1S-(phenylmethyl)propyl]-carbamate. Columnchromotography on silica gel eluting with chloroform containing 1%ethanol afforded the pure product. Anal. Calcd for C₂₉H₃₆N₂O₅S: C,66.39; H, 6.92; N, 5.34. Found: C, 66.37; H, 6.93; N, 5.26.

EXAMPLE 21

[0227]

[0228] Preparation of2R-hydroxy-3-[[(4-aminophenyl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylamine

[0229] Part A: Preparation of Carbamic Acid,2R-hydroxy-3-[[(4-nitrophenyl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl-,Phenylmethyl Ester

[0230] To a solution of 4.0 g (10.8 mmol) of N-[3S-benzyloxycarbonylamino-2R-hydroxy-4-phenyl]-N-isobutylamine in 50 mL of anhydrousmethylene chloride, was added 4.5 mL (3.27 g, 32.4 mmol) oftriethylamine. The solution was cooled to 0° C. and 2.63 g (11.9 mmol)of 4-nitrobenzene sulfonyl chloride was added, stirred for 30 minutes at0° C., then for 1 hour at room temperature. Ethyl acetate was added,washed with 5% citric acid, saturated sodium bicarbonate, brine, driedand concentrated to yield 5.9 g of crude material. This wasrecrystallized from ethyl acetate/hexane to afford 4.7 g of purecarbamic acid, [2R-hydroxy-3-[[(4-nitrophenyl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl-, phenylmethyl ester, m/e=556(M+H).

[0231] Part B: Preparation of 2R-hydroxy-3-[[(4-aminophenyl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylamine

[0232] A solution of 3.0 g (5.4 mmol) of carbamic acid,2R-hydroxy-3-[[(4-nitrophenyl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl-, phenylmethyl ester in 20 mL of ethylacetate was hydrogenated over 1.5 g of 10% palladium-on-carbon catalystunder 35 psig of hydrogen for 3.5 hours. The catalyst was removed byfiltration and the solution concentrated to afford 2.05 g of the desired2R-hydroxy-3-[[(4-aminophenyl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylamine,m/e=392(M+H).

EXAMPLE 22

[0233]

[0234] Preparation of2R-hydroxy-3-[[(3-aminophenyl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylamine

[0235] Part A: Preparation of Carbamic Acid,[2R-hydroxy-3-[(3-nitrophenylsulfonyl)(2-methylpropyl)amino]-1S-(phenylmethyl)propyl-,Phenylmethyl Ester

[0236] To a solution of 1.1 g (3.0 mmol) of N-[3S-benzyloxycarbonylamino-2R-hydroxy-4-phenyl]-N-isobutylamine in 15 mL of anhydrousmethylene chloride, was added 1.3 mL (0.94 g, 9.3 mmol) oftriethylamine. The solution was cooled to 0° C. and 0.67 g (3.0 mmol) of3-nitrobenzene sulfonyl chloride was added, stirred for 30 minutes at 0°C., then for 1 hour at room temperature. Ethyl acetate was added, washedwith 5% citric acid, saturated sodium bicarbonate, brine, dried andconcentrated to yield 1.74 g of crude material. This was recrystallizedfrom ethyl acetate/hexane to afford 1.40 g of pure carbamic acid,[2R-hydroxy-3-[(3-nitrophenylsulfonyl)(2-methylpropyl)amino]-1S-(phenylmethyl)propyl-, phenylmethyl ester, m/e=562(M+Li).

[0237] Part B: Preparation of[2R-hydroxy-3-[[(3-aminophenyl)sulfonyl](2-methylpropyl)amino)-1S-(phenylmethyl)propylamine

[0238] A solution of 1.33 g (2.5 mmol) of carbamic acid,[2R-hydroxy-3-[(3-nitrophenylsulfonyl)(2-methylpropyl)amino]-1S-(phenylmethyl)propyl-,phenylmethyl ester in 40 mL of 1:1 methanol/tetrahydrofuran washydrogenated over 0.70 g of 10% palladium-on-carbon catalyst under 40psig of hydrogen for 1.5 hours. The catalyst was removed by filtrationand the solution concentrated to afford 0.87 g of the desired[2R-hydroxy-3-[[(3-aminophenyl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylamine.

EXAMPLE 23

[0239]

[0240] Preparation of2R-hydroxy-3-[(2,3-dihydrobenzofuran-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylamine

[0241] Part A: Preparation of 5-(2,3-dihydrobenzofuranyl)sulfonylChloride

[0242] To a solution of 3.35 g of anhydrous N,N-dimethylformamide at 0°C. under nitrogen was added 6.18 g of sulfuryl chloride, whereupon asolid formed. After stirring for 15 minutes, 4.69 g of2,3-dihydrobenzofuran was added, and the mixture heated at 100° C. for 2hours. The reaction was cooled, poured into ice water, extracted withmethylene chloride, dried over magnesium sulfate, filtered andconcentrated the crude material. This was recrystallized from ethylacetate to afford 2.45 g of 5-(2,3-dihydrobenzofuranyl)sulfonylchloride.

[0243] Part B: Preparation of Carbamic acid,2R-hydroxy-3-[[(2,3-dihydrobenzofuran-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl-, phenylmethyl Ester

[0244] To a solution of 1.11 g (3.0 mmol) of N-[3S-benzyloxycarbonylamino-2R-hydroxy-4-phenyl]-N-isobutylamine in 20 mL of anhydrousmethylene chloride, was added 1.3 mL (0.94 g, 9.3 mmol) oftriethylamine. The solution was cooled to 0° C. and 0.66 g of5-(2,3-dihydrobenzofuranyl) sulfonyl chloride was added, stirred for 15minutes at 0° C., then for 2 hour at room temperature. Ethyl acetate wasadded, washed with 5% citric acid, saturated sodium bicarbonate, brine,dried and concentrated to yield 1.62 g of crude material. This wasrecrystallized from diethyl ether to afford 1.17 g of pure carbamicacid,[2R-hydroxy-3-[[(2,3-dihydrobenzofuran-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl-,phenylmethyl ester.

[0245] Part C: Preparation of [2R-hydroxy-3-[[(2,3-dihydrobenzofuran-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylamine

[0246] A solution of 2.86 g of carbamic acid,[2R-hydroxy-3-[[(2,3-dihydrobenzofuran-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl-, phenylmethyl ester in 30 mL oftetrahydrofuran was hydrogenated 0.99 g of 10% palladium-on-carbon under50 psig of hydrogen for 16 hours. The catalyst was removed by filtrationand the filtrate concentrated to afford 1.99 g of the desired[2R-hydroxy-3-[[(2,3-dihydrobenzofuran-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylamine.

EXAMPLE 24

[0247]

[0248] Preparation ofN-[(1,1-dimethylethoxyl)carbonyl]-N-[2-methylpropyl]-3S-[N¹-(phenylmethoxycarbonyl)amino]-2R-hydroxy-4-phenylbutylamine

[0249] To a solution of 7.51 g (20.3 mmol) ofN-[3S-[(phenylmethoxycarbonyl)amino]-2R-hydroxy-4-phenylbutyl]-2-methylpropylaminein 67 mL of anhydrous tetrahydrofuran was added 2.25 g (22.3 mmol) oftriethylamine. After cooling to 0° C., 4.4 g (20.3 mmol) ofdi-tert-butyldicarbonate was added and stirring continued at roomtemperature for 21 hours. The volatiles were removed in vacuo, ethylacetate added, then washed with 5% citric acid, saturated sodiumbicarbonate, brine, dried over magnesium sulfate, filtered andconcentrated to afford 9.6 g of crude product. Chromatography on silicagel using 30% ethyl acetate/hexane afforded 8.2 g of pureN-[[3S-(phenylmethylcarbamoyl)amino]-2R-hydroxy-4-phenyl]-1-[(2-methylpropyl)amino-2-(1,1-dimethylethoxyl)carbonyl]butane,mass spectum m/e=477 (M+Li).

EXAMPLE 25

[0250]

[0251] Preparation ofN¹-[2R-hydroxy-3-[N²-(3-methyl-butyl)-N²-(phenylsulfonyl)amino]-1S-(phenylmethyl)propyl]-2S-amino-3,3-dimethylbutaneamide

[0252] Part A:

[0253] To a solution of N-CBZ-L-tert-leucine (450 mg, 1.7 mmol) andN-hydroxybenzotriazole (260 mg, 1.7 mmol) in DMF (10 mL) was added EDC(307 mg, 1.6 mmol). The solution was stirred for 60 minutes at roomtemperature and then2R-hydroxy-3-[N-(3-methylbutyl)-N-(phenylsulfonyl)amino]-1S-(phenylmethyl)propylamine(585 mg, 1.5 mmol) in DMF (2 mL) was added. The reaction was stirred for16 hours at room temperature, then poured into a 50% saturated solutionof sodium bicarbonate (200 mL). The aqueous mixture was extracted thricewith ethyl acetate (50 mL). The combined ethyl acetate layers werewashed with water (50 mL) and saturated NaCl solution (50 mL), thendried over magnesium sulfate. Filtration and concentration produced anoil which was chromatographed on silica gel (50 gm) eluting with 20%ethyl acetate in hexane. The phenylmethyl[1S-[[[2R-hydroxy-3-[(3-methylbutyl)(phenylsulfonyl)amino]-1S-(phenylmethyl)propyl]amino]carbonyl]-2,2-dimethylpropyl]carbamate was obtained as a solid Anal.

[0254] Calcd for C₃₅H₄₇N₃O₆S: C, 65.91; H, 7.43; N, 6.59. Found: C,65.42; H, 7.24; N, 6.55.

[0255] Part B:

[0256] A solution of phenylmethyl[1S-[[[2R-hydroxy-3-[(3-methylbutyl)(phenylsulfonyl)-amino]-1S-(phenylmethyl)propyl]amino]carbonyl]-2,2-dimethylpropyl]carbamate(200 mg, 0.31 mmol) in methanol (15 mL) was hydrogenated over 10%palladium on carbon for 2 hours. The reaction was filtered throughdiatomaceous earth and concentrated to an oil.

EXAMPLE 26

[0257]

[0258] Preparation ofN¹-[2R-hydroxy-3-[N²-(2-methylbutyl)-N²-(phenylsulfonyl)amino]-1S-(phenylmethyl)propyl]-2S-amino-3S-methylpentanamide.hydrochlorideSalt

[0259] Part A:

[0260] To a solution of2R-hydroxy-3-[N-(3-methylbutyl)-N-(phenylsulfonyl)amino]-1S-(phenylmethyl)propylamine (2.79 g, 7.1 mmol) in 27 mL of dioxane was added (2.3 g, 7.1mmol) of N-t-butylcarbonyl-L-isoleucine-N-hydroxysuccinamide ester, andthe reaction was stirred under nitrogen atmosphere for 16 hours. Thecontents of the reaction were concentrated in vacuo, and the residuedissolved in ethyl acetate, washed with potassium hydrogen sulfate (5%aqueous), saturated sodium bicarbonate, and saturated sodium chloride.The organic layer was dried over magnesium sulfate, filtered andconcentrated to yield 4.3 grams of crude material which waschromatographed using 3:1 ethyl acetate:hexane to obtain 3.05 g, 72%yield of Pentanamide,2S-[[(1,1-dimethylethoxy)carbonyl]amino]-N-[2R-hydroxy-3-[(3-methylbutyl)phenylsulfonyl)amino]-1S-(phenylmethyl)propyl]-3-methyl-.

[0261] Part B

[0262] (3.05 g, 5.0 mmol) of the product from Part A was dissolved in 20mL of 4N HCl in dioxane and stirred under nitrogen atmosphere for 1.5hours. The contents were concentrated in vacuo, and chased with diethylether. The crude hydrochloride salt was pumped on at 1 mm Hg until dryto yield 2.54 g of product as its hydrochloride salt.

EXAMPLE 27

[0263]

[0264] Preparation ofN¹-[2R-hydroxy-3-[N²-(2-methylpropyl)-N²-(4-methoxyphenylsulfonyl)amino]-1S-(phenylmethyl)propyl]-2S-amino-3S-methylpentanamide

[0265] Part A:

[0266] To a solution of 2R-hydroxy-3-[(2-methylpropyl)(4-methoxyphenylsulfonyl)amino]-1S-(phenylmethyl) propylamine (1.70 g,4.18 mmol) in 40 mL of dichloromethane was addedN-carbobenzyloxy-L-isoleucine-N-hydroxysuccinamide ester (1.51 g, 4.18mmol) and the solution stirred under nitrogen atmosphere for 16 hours.The contents were concentrated in vacuo and the residue was redissolvedin ethyl acetate. The ethyl acetate solution was washed with an aqueoussolution of 5% KHSO₄, saturated sodium bicarbonate, and saturated sodiumchloride, dried over magnesium sulfate, filtered, and concentrated toyield 2.47 g of crude product. The product was purified by silica gelchromatography using 1 2:1 hexane:ethyl acetate eluant to yield 2.3 g.(84% yield) of2S-[(carbobenzyloxy)amino]-N-[2R-hydroxy-3-[(3-methylpropyl)(4-methoxyphenylsulfonyl)amino]-1S-(phenylmethyl)propyl]-3S-methylpentanamide.

[0267] Part B:

[0268] (1.18 g, 1.8 mmol) of the product from Part A was dissolved in 50mL of methanol, and to this was added 250 mg of 10% Palladium on Carbonwhile under a stream of nitrogen. The suspension was hydrogenated using50 psig of hydrogen for 20 hours. The contents were purged with nitrogenand filtered through celite, and concentrated in vacuo to yield 935 mgof 2S-(amino)-N-[2R-hydroxy-3-[(3-methylpropyl)(4-methoxyphenylsulfonyl)amino]-1S-(phenylmethyl)propyl]-3S-methylpentanamide, which was usedwithout further purification.

EXAMPLE 28

[0269]

[0270] Preparation of Carbamic Acid,2R-hydroxy-3-[[(2-aminobenzothiazol-6-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl-,Phenylmethyl Ester

[0271] Carbamic acid,2R-hydroxy-3-[[(4-aminophenyl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl-,phenylmethyl ester 0.30 g (0.571 mmol) was added to a well mixed powderof anhydrous copper sulfate (1.20 g) and potassium thiocyanate (1.50 g)followed by dry methanol (6 mL) and the resulting black-brown suspensionwas heated at reflux for 2 hrs. The reaction mixture was filtered andthe filtrate was diluted with water (5 mL) and heated at reflux. Ethanolwas added to the reaction mixture, cooled and filtered. The filtrateupon concentration afforded a residue which was chromatographed (ethylacetate:hexane 80:20) to afford 0.26 g (78%) of the desired compound asa solid.

EXAMPLE 29

[0272]

Preparation of Carbamic Acid,2R-hydroxy-3-[[(benzothiazol-6-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl-, phenylmethyl Ester

[0273] Method 1:

[0274] Carbamic acid,2R-hydroxy-3-[[(2-aminobenzothiazol-6-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl-, phenylmethyl ester (0.25 g, 0.429 mmol) was added to a solutionof isoamylnitrite (0.116 mL, 0.858 mmol) in dioxane (5 mL) and themixture was heated at 85° C. After the cessation of evolution ofnitrogen, the reaction mixture was concentrated and the residue waspurified by chromatography (hexane:ethyl acetate 5:3) to afford 0.130 g(53%) of the desired product as a solid.

[0275] Method 2:

[0276] Crude benzothiazole-6-sulfonyl chloride in ethyl acetate (100 mL)was added to N-[3S-benzyloxycarbonylamino-2R-hydroxy-4-phenyl]-N-isobutylamine (1.03 g, 2.78 mmol) followedby N-methylmorpholine (4 mL). After stirring at room temperature for 18hr., the reaction mixture was diluted with ethyl acetate (100 mL),washed with citric acid (5%, 100 mL), sodium bicarbonate (saturated, 100mL) and brine (100 mL), dried (MgSO₄) and concentrated in vacuo. Theresidue was chromatographed (silica gel, ethyl acetate:hexane 1:1) toafford 0.340 g (23%) of desired product.

EXAMPLE 30

[0277]

[0278] Preparation of Carbamic Acid, 2R-hydroxy-3-[[(2-aminobenzothiazol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl-,Phenylmethyl Ester; and Carbamic Acid,2R-hydroxy-3-[[(2-aminobenzothiazol-7-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl-,Phenylmethyl Ester

[0279] The carbamic acid, 2R-hydroxy-3-[(3-aminophenylsulfonyl)(2-methylpropyl)amino]-1S-(phenylmethyl)propyl-, phenylmethyl ester 0.36g (0.685 mmol) was added to a well mixed powder of anhydrous coppersulfate (1.44 g) and potassium thiocyanate (1.80 g) followed by drymethanol (10 mL) and the rsulting black-brown suspension was heated atreflux for 2 hrs. The reaction mixture was filtered and the filtrate wasdiluted with water (5 mL) and heated at reflux. Ethanol was added to thereaction mixture, cooled and filtered. The filtrate upon concentrationafforded a rseidue which was chromatographed (ethyl acetate:hexane 1:1)to afford 0.18 g (45%) of the 7-isomer as a solid. Further elution ofthe column with (ethyl acetate:hexane 3:2) afforded 0.80 g (20%)afforded the 5-isomer as a solid.

EXAMPLE 31

[0280]

[0281] Preparation of3S-amino-1-[N-(2-methylpropyl)-N-(4-methoxyphenylsulfonyl)amino]-4-phenyl-2R-butanol

[0282] Part A:N-benzyloxycarbonyl-3(S)-amino-1-chloro-4-phenyl-2(S)-butanol

[0283] To a solution of N-benzyloxycarbonyl-L-phenylalanine chloromethylketone (75 g, 0.2 mol) in a mixture of 800 mL of methanol and 800 mL oftetrahydrofuran was added sodium borohydride (13.17 g, 0.348 mol, 1.54equiv.) over 100 min. The solution was stirred at room temperature for 2hours and then concentrated in vacuo. The residue was dissolved in 1000mL of ethyl acetate and washed with 1N KHSO₄, saturated aqueous NaHCO₃,saturated aqueous NaCl, dried over anhydrous MgSO₄, filtered andconcentrated in vacuo to give an oil. The crude product was dissolved in1000 mL of hexanes at 60° C. and allowed to cool to room temperaturewhere upon crystals formed that were isolated by filtration and washedwith copious amounts of hexanes. This solid was then recrystallized fromhot ethyl acetate and hexanes to provide 32.3 g 43% ofN-benzyloxycarbonyl-3(S)-amino-1-chloro-4-phenyl-2(S)-butanol, mp150-151° C., FAB MS: MLi+=340.

[0284] Part B:3(S)-[N-(benzyloxycarbonyl)amino]-1,2(S)-epoxy-4-phenylbutane

[0285] A solution of potassium hydroxide (6.52 g. 0.116 mol, 1.2 equiv.)in 970 mL of absolute ethanol was treated withN-benzyloxycarbonyl-3(S)-amino-1-chloro-4-phenyl-2(S)-butanol (32.3 g,0.097 mol). This solution was stirred at room temperature for 15 minutesand then concentrated in vacuo to give a white solid. The solid wasdissovled in dichloromethane and washed with water, dried over anhydMgSO₄, filetered and concentrated in vacuo to give a white solid. Thesolid was crystallized from hexanes and ethyl acetate to give 22.3 g,77% of 3(S)-[N-(benzyloxycarbonyl)amino]-1,2(S)-epoxy-4-phenylbutane, mp102-103° C., FAB MS: MH⁺=298.

[0286] Part C:N-[3(S)-benzyloxycarbonylamino-2(R)-hydroxy-4-phenyl]N-isobutylamine

[0287] A solution of N-benzylcarbonyl-3(S)-amino-1,2-(S)-epoxy-4-phenylbutane (50.0 g, 0.168 mol) and isobutylamine (246 g, 3.24 mol, 20equivalents) in 650 mL of isopropyl alcohol was heated to reflux for1.25 hours. The solution was cooled to room temperature, concentrated invacuo and then poured into 1 L of stirring hexane whereupon the productcrystallized from solution. The product was isolated by filtration andair dried to give 57.56 g, 92% ofN[3(S)-benzyloxycarbonylamino-2(R)-hydroxy-4-phenyl]-N-isobutylamine, mp108.0-109.5° C., MH+ m/z=371.

[0288] Part D: phenylmethyl[2(R)-hydroxy-3-[N-(2-methylpropyl)-N-(4-methoxyphenylsulfonyl)amino]-1S-(phenylmethyl)propyl]carbamate

[0289] The amine from Part C (936.5 mg, 2.53 mmol) and triethylamine(2.88.5 mg, 2.85 mmol) was dissolved in 20 mL of dichloromethane andtreated with 4-methoxybenzenesulfonyl chloride (461 mg, 2.61 mmol). Thesolution was stirred at room temperature for 16 hours and thenconcentrated in vacuo. The residue was dissolved in ethyl acetate andthis solution was washed with 1N KHSO₄, saturated aqueous NaHCO₃, brine,dried over anhyd MgSO₄, filtered, and concentrated to give a clear oil1.234 g. The oil was crystallized from a mixture of ether and hexanes,729.3 mg, 56.5% mp 95-99° C., FAB MS: MH⁺=511.

[0290] Part E:3S-amino-1-[N-(2-methylpropyl)-N-(4-methoxyphenylsulfonyl)amino]-4-phenyl-2R-butanol

[0291] A solution of phenylmethyl[2(R)-hydroxy-3-[N-(2-methylpropyl)-N-(4-methoxyphenylsulfonyl)amino]1-S-(phenylmethyl)propylcarbamate (671.1 mg, 1.31 mmol) from Part D in 10 mL of methanol washydrogenated over 50 mg of 10% palladium on carbon at 40 psig at roomtemperature for 15 hours. The catalyst was removed by filtration throughdiatomaceous earth and the filtrate concentrated to give a white foam,474.5 mg, 96%, FAB MS: MH⁺=377.

EXAMPLE 32

[0292]

[0293] Preparation of 1.3-benzodioxole-5-sulfonyl Chloride

[0294] Method 1:

[0295] To a solution of 4.25 g of anhydrous N,N-dimethylformamide at 0°C. under nitrogen was added 7.84 g of sulfuryl chloride, whereupon asolid formed. After stirring for 15 minutes, 6.45 g of 1,3-benzodioxolewas added, and the mixture heated at 100° C. for 2 hours. The reactionwas cooled, poured into ice water, extracted with methylene chloride,dried over magnesium sulfate, filtered and concentrated to give 7.32 gof crude material as a black oil. This was chromatographed on silica gelusing 20% methylene chloride/hexane to afford 1.9 g of(1,3-benzodioxol-5-yl)sulfonyl chloride.

[0296] Method 2:

[0297] To a 22 liter round bottom flask fitted with a mechanicalstirrer, a cooling condenser, a heating mantle and a pressure equalizingdropping funnel was added sulfur trioxide DMF complex (2778 g, 18.1moles). Dichloroethane (4 liters) was then added and stirring initiated.1,3-Benzodioxole (1905 g, 15.6 moles) as then added through the droppingfunnel over a five minute period. The temperature was then raised to 75°C. and held for 22 hours (NMR indicated that the reaction was done after9 hours.) The reaction was cooled to 26° and oxalyl chloride (2290 g,18.1 moles) was added at a rate so as to maintain the temperature below40° C. (1.5 hours). The mixture was heated to 67° C. for 5 hoursfollowed by cooling to 16° C. with an ice bath. The reaction wasquenched with water (5 l) at a rate which kept the temperature below 20°C. After the addition of water was complete, the mixture was stirred for10 minutes. The layers were separated and the organic layer was washedagain twice with water (51). The organic layer was dried with magnesiumsulfate (500 g) and filtered to remove the drying agent. The solvent wasremoved under vacuum at 50° C. The resulting warm liquid was allowed tocool at which time a solid began to form. After one hour, the solid waswashed with hexane (400 mL), filtered and dried to provide the desiredsulfonyl chloride (2823 g). The hexane wash was concentrated and theresulting solid washed with 400 mL hexane to provide additional sulfonylchloride (464 g). The total yield was 3287 g (95.5% based upon1,3-benzodioxole).

[0298] Method 3:

[0299] 1,4-benzodioxan-6-sulfonyl chloride was prepared according to theprocedure disclosed in EP 583960, incorporated herein by reference.

EXAMPLE 33

[0300]

[0301] Preparation of1-[N-[(1,3-benzodioxol-5-yl)sulfonyl]-N-(2-methylpropyl)amino]-3(S)-[bis(phenylmethyl)amino]-4-phenyl-2(R)-butanol

[0302] Method 1:

[0303] To a 5000 mL, 3-necked flask fitted with a mechanical stirrer wasaddedN-[3(S)-[N,N-bis(phenylmethyl)amino]-2(R)-hydroxy-4-phenylbutyl]-N-isobutylamine.oxalicacid salt (354.7 g, 0.7 mole) and 1,4-dioxane (2000 mL). A solution ofpotassium carbonate (241.9 g, 1.75 moles) in water (250 mL) was thenadded. The resultant heterogeneous mixture was stirred for 2 hours atroom temperature followed by the addition of 1,3-benzodioxole-5-sulfonylchloride (162.2 g, 0.735 mole) dissolved in 1,4-dioxane (250 mL) over 15minutes. The reaction mixture was stirred at room temperature for 18hours. Ethyl acetate (1000 mL) and water (500 mL) were charged to thereactor and stirring continued for another 1 hour. The aqueous layer wasseparated and further extracted with ethyl acetate (200 mL). Thecombined ethyl acetate layers were washed with 25% brine solution (500mL) and dried over anhydrous magnesium sulfate. After filtering andwashing the magnesium sulfate with ethyl acetate (200 mL), the solventin the filtrate was removed under reduced pressure yielding the desiredsulfonamide as an viscous yellow foamy oil (440.2 g 105% yield). HPLC/MS(electrospray) (m/z 601 [M+H]⁺].

EXAMPLE 34

[0304]

[0305] Preparation of1-[N-[(1,3-benzodioxol-5-yl)sulfonyl]-N-(2-methylpropyl)amino]-3(S)-amino-4-phenyl-2(R)-butanol.methanesulfonicAcid Salt

[0306] Method 1:

[0307] Crude1-[N-[(1,3-benzodioxol-5-yl)sulfonyl]-N-(2-methylpropyl)amino]-3(S)-[bis(phenylmethyl)amino]-4-phenyl-2(R)-butanol(6.2 g, 0.010 moles) was dissolved in methanol (40 mL). Methanesulfonicacid (0.969 g, 0.010 moles) and water (5 mL) were then added to thesolution. The mixture was placed in a 500 mL Parr hydrogenation bottlecontaining 20% Pd(OH)₂ on carbon (255 mg, 50% water content). The bottlewas placed in the hydrogenator and purged 5 times with nitrogen and 5times with hydrogen. The reaction was allowed to proceed at 35° C. with63 PSI hydrogen pressure for 18 hours. Additional catalyst (125 mg) wasadded and, after purging, the hydrogenation continued for and additional20 hours. The mixture was filtered through celite which was washed withmethanol (2×10 mL). Approximately one third of the methanol was removedunder reduced pressure. The remaining methanol was removed by aziotropicdistillation with toluene at 80 torr. Toluene was added in 15, 10, 10and 10 mL portions. The product crystallized from the mixture and wasfiltered and washed twice with 10 mL portions of toluene. The solid wasdried at room temperature at 1 torr for 6 hours to yield the amine salt(4.5 g, 84%). HPLC/MS (electrospray) was consistent with the desiredproduct (m/z 421 [M+H]⁺).

[0308] Method 2:

[0309] Part A:N-[3(S)-[N,N-bis(phenylmethyl)amino]-2(R)-hydroxy-4-phenylbutyl]-N-isobutylamine.oxalicacid salt (2800 g, 5.53 moles) and THF (4L) were added to a 22L roundbottom flask fitted with a mechanical stirrer. Potassium carbonate (1921g, 13.9 moles) was dissolved in water (2.8L) and added to the THFslurry. The mixture was then stirred for one hour.1,3-benzodioxole-5-sulfonyl chloride (1281 g, 5.8 moles) was dissolvedin THF (1.4L) and added to the reaction mixture over 25 minutes. Anadditional 200 mL of THF was used to rinse the addition funnel. Thereaction was allowed to stir for 14 hours and then water (4 L) wasadded. This mixture was stirred for 30 minutes and the layers allowed toseparate. The layers was removed and the aqueous layer washed twice withTHF (500 mL). The combined THF layers were dried with magnesium sulfate(500 g) for one hour. This solution was then filtered to remove thedrying agent and used in subsequent reactions.

[0310] Part B: To the THF solution of crude1-[N-[(1,3-benzodioxol-5-yl)sulfonyl]-N-(2-methylpropyl)amino]-3(S)-[bis(phenylmethyl)amino]-4-phenyl-2(R)-butanolwas added water (500 mL) followed by methane sulfonic acid (531 g, 5.5moles). The solution was stirred to insure complete mixing and added toa 5 gallon autoclave. Pearlman's catalyst (200 g of 20% Pd(OH)₂ on C/50%water) was added to the autoclave with the aid of THF (500 mL). Thereactor was purged four times with nitrogen and four times withhydrogen. The reactor was charged with 60 psig of hydrogen and stirringat 450 rpm started. After 16 hours, HPLC analysis indicated that a smallamount of the mono-benzyl intermediate was still present. Additionalcatalyst (50 g) was added and the reaction was allowed to run overnight.The solution was then filtered through celite (500 g) to remove thecatalyst and concentrated under vacuum in five portions. To eachportion, toluene (500 mL) was added and removed under vacuum toazeotropically removed residual water. The resulting solid was dividedinto three portions and each washed with methyl t-butyl ether (2 L) andfiltered. The residual solvent was removed at room temperature in avacuum oven at less than 1 torr to yield the 2714 g of the expectedsalt.

[0311] If desired, the product can be further purified by the followingprocedure. A total of 500 mL of methanol and 170 g of material fromabove was heated to reflux until it all dissolved. The solution wascooled, 200 mL of isopropanol added and then 1000-1300 mL of hexane,whereupon a white solid precipitated. After cooling to 0° C., thisprecipitate was collected and washed with hexane to afford 123 g of thedesired material. Through this procedure, the original material whichwas a 95:5 mixture of alcohol diastereomers was greater than 99:1 of thedesired diastereomer.

EXAMPLE 35

[0312]

[0313] Preparation of2R-hydroxy-3-[[(1.3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylamine

[0314] Part A: Preparation of2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylcarbamic Acid Phenylmethyl Ester

[0315] To a solution of 3.19 g (8.6 mmol) of N-[3S-benzyloxycarbonylamino-2R-hydroxy-4-phenyl]-N-isobutylamine in 40 mL of anhydrousmethylene chloride, was added 0.87 g of triethylamine. The solution wascooled to 0° C. and 1.90 g of (1,3-benzodioxol-5-yl)sulfonyl chloridewas added, stirred for 15 minutes at 0° C., then for 17 hours at roomtemperature. Ethyl acetate was added, washed with 5% citric acid,saturated sodium bicarbonate, brine, dried and concentrated to yieldcrude material. This was recrystallized from diethyl ether/hexane toafford 4.77 g of pure2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylcarbamicacid phenylmethyl ester.

[0316] Part B: Preparation of2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylamine

[0317] A solution of 4.11 g of carbamic acid,2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl-,phenylmethyl ester in 45 mL of tetrahydrofuran and 25 mL of methanol washydrogenated over 1.1 g of 10% palladium-on-carbon under 50 psig ofhydrogen for 16 hours. The catalyst was removed by filtration and thefiltrate concentrated to afford 1.82 g of the desired2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylamine.

EXAMPLE 36

[0318]

[0319] Preparation of Benzothiazole-6-sulfonyl Chloride

[0320] Part A: Preparation of N-(4-Sulfonamidophenyl)thiourea

[0321] A mixture of sulfanilamide (86 g, 0.5 mole), ammonium thiocyanate(76.0 g, 0.5 mole) and dilute hydrochloric acid (1.5 N, 1 L) wasmechanically stirred and heated at reflux for 2 hr. About 200 mL ofwater was distilled off and concentration of the reaction mixtureafforded a solid. The solid was filtered and was washed with cold waterand air dried to afford 67.5 g (59%) of the desired product as a whitepowder.

[0322] Part B: Preparation of 2-Amino-6-sulfonamidobenzothiazole

[0323] Bromine (43.20 g, 0.27 mol) in chloroform (200 mL) was added over1 hr. to a suspension of N-(4-sulfonamidophenyl)-thiourea (27.72, 0.120mol) in chloroform (800 mL). After the addition, the reaction mixturewas heated at reflux for 4.5 hr. The chloroform was removed in vacuo andthe residue was repeatedly distilled with additional amounts ofchloroform. The solid obtained was treated with water (600 mL) followedby ammonium hydroxide (to make it basic), then was heated at reflux for1 hr. The cooled reaction mixture was filtered, washed with water andair dried to afford 22.0 g (80%) of the desired product as a whitepowder.

[0324] Part C: Preparation of Benzothiazole-6-sulfonic Acid

[0325] A suspension of 2-amino-6-sulfonamido-benzothiazole (10.0 g,43.67 mmol) in dioxane (300 mL) was heated at reflux. Isoamylnitrite (24mL) was added in two portions to the reaction mixture. Vigorousevolution of gas was observed (the reaction was conducted behind ashield as a precaution) and after 2 hr., a red precipitate was depositedin the reaction vessel. The reaction mixture was filtered hot, and thesolid was washed with dioxane and was dried. The solid wasrecrystallized from methanol-water. A small amount of a precipitate wasformed after 2 days. The precipitate was filtered off and the motherliquor was concentrated in vacuo to afford a pale red-orange solid (8.0g, 85%) of pure product.

[0326] Part D: Preparation of 6-Chlorosulfonylbenzothiazole

[0327] Thionyl chloride (4 mL) was added to a suspension of thebenzothiazole-6-sulfonic acid (0.60 g, 2.79 mmol) in dichloroethane (15mL) and the reaction mixture was heated at reflux and dimethylformamide(5 mL) was added to the reaction mixture to yield a clear solution.After 1.5 hr. at reflux, the solvent was removed in vacuo and excess HCland thionyl chloride was chased by evaporation with dichloroethane.

EXAMPLE 37

[0328]

[0329] Preparation of N-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[(2S-pyrrolidinylcarbonyl)amino]-3,3-dimethylbutanamide.hydrochloride Salt

[0330] Part A: Preparation ofN-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[(phenylmethoxycarbonyl)amino]-3,3-dimethylbutanamide

[0331] To a solution of 118.8 g (0.776 mol) of N-hydroxybenzotriazoleand 137.1 g (0.52 mol) of N-carbobenzyloxycarbonyl-L-tert-leucine in 750mL of anhydrous DMF at 0° C. under a nitrogen atmosphere, was added109.1 g (0.57 mol) of EDC. After stirring at 0° C. for 2 hours, asolution of 273 g (0.53 mol) of2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylaminemethanesulfonate, previously neutralized with 228 mL (210 g, 2.08 mol)of 4-methylmorpholine, in 250 mL of anhydrous DMF was added. Afterstirring at 0° C. for 30 minutes, the mixture stirred at roomtemperature for 18 hours. The solvents were removed under reducedpressure at 45° C., 1.5 L of ethyl acetate added, washed with 5% citricacid, saturated sodium bicabonate, brine, dried over anhydrous magnesiumsulfate, filtered and concentrated to afford 400 g of crude material.This was chromatographed in 3 batches on a Prep 2000 Chromatogram onsilica gel using 20%-50% ethyl acetate/hexane as eluent to yield 320 gof purified material, m/e=674 (M+Li), 98% by HPLC.

[0332] Part B: Preparation ofN-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-amino-3,3-dimethylbutanamide

[0333] A solution of 312 g of the Cbz compound from above in 1L oftetrahydrofuran was hydrogenated in the presence of 100 g of 4%palladium-on-carbon catalyst under 60 psig of hydrogen for 6 hours atroom temperature. The catalyst was removed by filtration and thesolvents removed under reduced pressure to afford 240 g of the desiredcompound.

[0334] Part C: Preparation ofN-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[[1-(phenylmethoxycarbonyl)pyrrolidin-2S-ylcarbonyl]amino]-3,3-dimethylbutanamide

[0335] A 250 mL round bottom flask equipped with magnetic stir bar andN₂ inlet was charged with 1.6 g Cbz-L-Proline (1.15 eq.) in 40 mL DMF.The reaction mixture was cooled to 0° C. and charged with 0.88 g HoBt(1.5 eq.) and 1.25 g EDC (1.15 eq.). The reaction was stirred 40 minutesat room temperature then a solution of 3.0 g of2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl amine and 1.85 mL N-methylmorpholine (3.0eq.) in 40 mL DMF was added. The reaction was stirred overnight. Thereaction was concentrated in vacuo and the residue was partitionedbetween ethyl acetate and saturated aqueous sodium bicarbonate. Theorganic layers were washed with 5% aqueous potassium hydrogen sulfateand brine, dried over Na₂SO₄, and concentrated in vacuo to yield 4.25 g(95%) of a white foam; RP HPLC>97% purity.

[0336] Part D: Preparation ofN-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[(2S-pyrrolidinylcarbonyl)amino]-3,3-dimethylbutanamide.hydrochloride Salt

[0337] A 300 mL Fisher-Porter vessel equipped with magnetic stir bar wascharged withN-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[[1-(phenylmethoxycarbonyl)pyrrolidin-2S-ylcarbonyl]amino]-3,3-dimethylbutanamide (1.15 g) and 10% Pd-C (wet) in150 mL MeOH. The reaction was hydrogenated at 50 psi for 6 hrs. thenfiltered thru Celite. The filtrate was concentrated in vacuo to 3.36 gof a white foam. The residue was taken up in 50 mL CH₃CN and treatedwith 0.96 mL (2 eq.) concentrated HCl. The reaction was conentrated invacuo to a solid, triturated with ether, and filtered to yield 3.1 g ofpure desired product.

EXAMPLE 38

[0338] Preparation of N-f2R-hydroxy-3-[[([1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-amino-3S-methylpentanamide.hydrochlorideSalt

[0339] Part A: Preparation ofN-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[[(1,1-dimethylethoxy)carbony]amino]-3S-methylpentanamide

[0340] To a cooled solution of N-t-Boc-L-isoleucine 2.02 g (8.74 mmol)and 2.00 g (13.11 mmol) of N-hydroxybenzotriazole in 17 mL ofN,N-dimethylformamide was added 1.84 g (9.61 mmol) of EDC and stirred at0° C. for one hour. To this was added a solution of 3.67 g (8.74 mmol)of 2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl amine in 6 mL of N,N-dimethylformamideand the solution stirred for 16 hours. The solvent was removed in vacuo,replaced with ethyl acetate, and washed with saturated sodiumbicarbonate, 5% citric acid and brine. The organic layers were driedover magnesium sulfate, filtered and concentrated to yield 6.1 grams ofcrude product, which was chromatoraphed on silica gel using 1:1 ethylacetate:hexane eluant to produce 4.3 g (78% yield) ofN-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[[(1,1-dimethylethoxy)carbonyl]amino]-3S-methylpentanamide.

[0341] Part B: Preparation ofN-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-amino-3S-methylpentanamide.hydrochlorideSalt

[0342]N-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[[(1,1-dimethylethoxy)carbonyl]amino]-3S-methylpentanamide(4.29 g, 6.77 mmol) was dissolved in 20 mL of 4N HCl in dioxane andstirred for 20 minutes. The precipitated product was stripped two timesfrom diethyl ether and the crude hydrochloride salt was used insubsequent reactions.

EXAMPLE 39

[0343] Preparation ofN-[2R-hydroxy-3-[[([1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[(2S-pyrrolidinylcarbonyl)amino]-3S-methylPentanamide

[0344] Part A: Preparation ofN-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[[1-(phenylmethoxycarbonyl)pyrrolidin-2S-ylcarbonyl]amino]-3S-methylpentanamide

[0345] A solution of 0.5 grams (2.2 mM) of N-CBZ-L-proline in 10 mL ofanhydrous DMF was cooled. to 0° C. and charged with 0.4 grams (2.8 mm)of HOBT and 0.4 grams (2.2 mM) of EDC. The ice bath was removed after 20minutes and stirring was continued for an additional 40 minutes. Asolution of 1.0 grams (1.9 mM) ofN-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-amino-3S-methylpentanamide.hydrochloridesalt and 0.6 grams (5.6 mM) of 4-methylmorpholine in 15 mL of anhydrousDMF was added and the mixture was stirred for 15 hours. The solventswere removed in vacuo and the residue was partitioned between 150 mL ofethyl acetate and 50 mL of 5% potassium hydrogen sulfate solution. Thelayers were separated, and the organic layer was washed with 50 mL eachof saturated sodium bicarbonate solution, water, and brine, then driedover anhydrous magnesium sulfate, filtered and concentrated in vacuo toafford 1.5 grams of crude material. Purification was accomplished byflash chromatography on silica gel using 70-80% ethyl acetate/hexane toyield 1.3 grams (90%) of the desired product as a white solid, m/e=771(M+Li).

[0346] Part B: Preparation ofN-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl]amino)-1S-(phenylmethyl)propyl]-2S-[(2S-pyrrolidinylcarbonyl)amino]-3S-methylpentanamide

[0347] A Fischer-Porter bottle equipped with a magnetic stir bar wascharged with 1.2 grams (1.5 mM) of the product from Part A and 25 mL ofTHF. The solution was hydrogenated in the presence of 1 gram of 10%palladium-on-carbon catalyst (50% water by weight) under 50 psig ofhydrogen for 16 hours at room temperature. The catalyst was removed byfiltration, and the solvents removed under reduced pressure to yield 0.9grams of the crude material. Purification was accomplished using flashchromatography on silica gel using 1-4% methanol/methylene chloride andyielded 0.8 grams (80%) of the desired product, m/e=637 (M+H)

EXAMPLE 40

[0348] Preparation ofN-[[2R-hydroxy-3-[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl]amino]-1S-(phenylmethyl)propyl-2S-amino-3-methylbutaneamide

[0349] Part A: Preparation ofN-[[2R-hydroxy-3-[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[(phenylmethoxycarbonyl)amino]-3-methylbutaneamide

[0350] A 250 mL round bottom flask equipped with magnetic stir bar wascharged with N-Cbz-L-Valine (4.22 g, 16.8 mmol) in 20 mL DMF. Thesolution was cooled to 0° C. and charged with HoBt (2.96, 21.9 mmol) andEDC (3.22 g, 16.8 mmol) and stirred 1 hour. The reaction was thencharged with N-methylmorpholine (1.7 g, 16.8 mmol),2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylamine(7.55 g, 14.6 mmol) in 30 mL of DMF. The reaction was stirred overnightat room temperature then concentrated in vacuo and partioned betweenethyl acetate and 5% Citric acid. The combined organic layers werewashed with saturated sodium bicarbonate and brine, and dried oversodium sulfate. Concentration in vacuo yielded 10 g crude product.Purification by Prep HPLC (20-40% ethyl acetate/hexane) yielded 5.8 g(61%) of the desired compound.

[0351] Part B: Preparation ofN-[[2R-hydroxy-3-[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-amino-3-methylbutaneamide

[0352] A 300 mL Fisher-Porter vessel equipped with magnetic stir bar wascharged withN-[[2R-hydroxy-3-[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[(phenylmethoxycarbonyl)amino]-3-methylbutaneamide(5.8 g), 2.3 g of 10% Pd-C in 75 mL tetrahydrofuran. The reaction wascharged with 50 psi H₂ and hydrogenated overnight. The reaction mixturewas filtered thru Celite and concentrated in vacuo to yield 4.4 g ofwhite foam that was used in subsequent reactions without furthurpurification.

EXAMPLE 41

[0353] Preparation ofN-[[2R-hydroxy-3-[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-amino-3-(methylsulfonyl)propaneamide.hydrochlorideSalt

[0354] Part A: Preparation ofN-[[2R-hydroxy-3-[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[[(1,1-dimethylethoxy)carbonyl]amino]-3-(methylthio)propaneamide

[0355] N-t-Boc-S-methyl-(L)-cysteine (2.80 g, 11.9 mmol),1-Hydroxybenzotriazole hydrate (1.92 g, 12.5 mmol), and1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (2.27 g,11.9 mmol) were mixed in N,N-dimethylformamide (30.0 mL) at 0° C. for 10min. N-Methylmorpholine (3.03 g, 33.0 mmol) was added and the solutionstirred an additional 10 min at 0° C.2R-Hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylamine(5.00 g, 11.9 mmol) was added and the solution was warmed to roomtemperature and stirred for 2 hours. The reaction mixture was pouredinto ethyl acetate (500 mL) and washed with 10% aqueous hydrochloricacid (3×100 mL), saturated aqueous sodium bicarbonate (3×100 mL) andbrine (2×100 mL). The organic layer was dried over sodium sulfate andpercolated through a bed of silica gel (50 g). The desired product (7.13g, 11.19 mmol, 93% yield) was obtained as a white solid by removal ofthe solvent at reduced pressure; m/e calcd 637; found (M+Li) 644.

[0356] Part B: Preparation ofN-[[2R-hydroxy-3-[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[[(1,1-dimethylethoxy)carbonyl]amino]-3-(methylsulfonyl)propaneamide

[0357]N-[[2R-hydroxy-3-[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[[(1,1-dimethylethoxy)carbonyl]amino]-3-(methylthio)propaneamide (7.10 g, 11.1 mmol) wasdissolved in methanol (150 mL). A solution of oxone® (20.8 g, 33.9 mmol)in water (150 mL) was added dropwise to the solution at room temperatureover 1.5 hours. The solution became cloudy and a precipitate formedduring the addition. The reaction was stirred for an additional 1 hourand tetrahydrofuran (200 mL) was added. After an additional 1 hour ofmixing the solution was poured into ethyl acetate (1000 mL) and washedwith water (3×200 mL) followed by brine (2×300 ml). The organic layerwas dried over anhydrous sodium sulfate and solvent removed at reducedpressure. The desired product (5.75 g, 8.86 mmol, 79% yield) wasobtained as an off white solid; m/e calcd 669; found (M+H) 670.

[0358] Part C: Preparation ofN-[[2R-hydroxy-3-[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-amino-3-(methylsulfonyl)propaneamide.hydrochloride Salt

[0359]N-[[2R-hydroxy-3-[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[[(1,1-dimethylethoxy)carbonyl]amino]-3-(methylsulfonyl)propaneamide (5.5 g, 8.20 mmol) was dissolved in dichloromethane (100mL) at room temperature. Anhydrous hydrochloric acid was bubbled throughthe solution for 15 min. The solution was stirred at room temperaturefor 2 hours and the solvent was removed at reduced pressure. The desiredproduct (4.91 g, 8.10 mmol, 99% yield) was obtained as a white solid;m/e calcd 569; found (M+Li) 576.

EXAMPLE 42

[0360] Preparation ofN-[[2R-hydroxy-3-[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-amino-3-methyl-3-(methylsulfonyl)butaneamide.hydrochlorideSalt

[0361] Part A: Preparation ofN-[[2R-hydroxy-3-[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[[(1,1-dimethylethoxy)carbonyl]amino]-3-methyl-3-(methylthio)butaneamide

[0362] The N-t-boc-S-methyl-L-penicillamine dicyclohexylamine salt (4.00g, 9.00 mmol), 1-Hydroxybenzotriazole hydrate (1.69 g, 11.00 mmol), and1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (1.71 g,9.00 mmol) were mixed in dimethylformamide (60.0 mL) at roomtemperature. The heterogeneous mixture was stirred for 1 hour and2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylamine(3.78 g, 9.00 mmol) was added and the heterogenous mixture was stirredfor 16 hours. The solution was poured into ethyl acetate (600 mL) andwashed With 10% aqueous acetic acid (2×300 mL), saturated aqueous sodiumbicarbonate (2×300 mL) and brine (300 mL). The solution was dried oversodium sulfate and the solvent was removed in vacuo The desired productwas purified by flash chromatography (0-80% ethyl acetate/hexanes onsilica gel). The product (5.21 g, 7.83 mmol, 87% yield) was obtained asa white foam; m/e calcd 665; found (M+Li) 672.

[0363] Part B: Preparation ofN-[[2R-hydroxy-3-[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[[(1,1-dimethylethoxy)carbonyl]amino]-3-methyl-3-(methylsulfonyl)butaneamide

[0364]N-[[2R-hydroxy-3-[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[[(1,1-dimethylethoxy)carbonyl]amino]-3-methyl-3-(methylthio)butaneamide(5.01 g, 7.53 mmol) was dissolved in tetrahydrofuran (250 mL). Asolution of oxone® (13.8 g, 22.6 mmol) in water (250 mL) was addeddropwise to the solution at room temperature over 2 hours. The solutionbecame cloudy and a precipitate formed during the addition. The solutionwas poured into ethyl acetate (500 mL) and washed with water (3×200 mL)followed by brine (2×300 mL). The organic layer was dried over anhydroussodium sulfate and solvent removed in vacuo.

[0365] The product (4.72 g, 6.77 mmol, 89% yield) was obtained as awhite foam; m/e calcd 697; found (M+Li) 704.

[0366] Part C: Preparation ofN-[[2R-hydroxy-3-[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-amino-3-methyl-3-(methylsulfonyl)butaneamide.hydrochlorideSalt

[0367]N-[[2R-hydroxy-3-[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[[(1,1-dimethylethoxy)carbonyl]amino]-3-methyl-3-(methylsulfonyl)butaneamide(4.51 g, 6.46 mmol) was dissolved in dichloromethane (200 mL) at roomtemperature. Anhydrous hydrochloric acid was bubbled through thesolution for 30 min. The solution was stirred at room temperature for 1hour and the solvent was removed in vacuo. The product (4.02 g, 6.35mmol, 99% yield) was obtained as a white solid; m/e calcd 697; found(M+Li) 704.

EXAMPLE 43

[0368] Preparation ofN-[2R-hydroxy-3-[[(1,1-dimethylethoxy)carbonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl-2S-amino-3,3-dimethylbutanamide

[0369] Part A: Preparation ofN-[(1,1-dimethylethoxyl)carbonyl]-N-[2-methylpropyl]-3S-[N¹-(phenylmethoxycarbonyl)amino]-2R-hydroxy-4-phenylbutylamine

[0370] A solution ofN-[3S-[N¹-(benzyloxycarbonyl)amino]-2R-hydroxy-4-phenylbutyl]-N-(2-methylpropyl)amine(18.5 g, 50 mmol), BOC-ON (12.35 g, 50 mmol) and triethylamine (7 mL) intetrahydrofuran (400 mL) was stirred at room temperature for 18 hoursand then concentrated in vacuo. The residue was dissolved indichloromethane (1 L) and washed with sodium hydroxide (5%, 2×200 mL)and brine, dried (MgSO₄) and then concentrated in vacuo to afford 23.5 g(quantitative yield) of the pure desired product.

[0371] Part B: Preparation of N-[2R-hydroxy-3-[[(1,1-dimethylethoxy)carbonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[(phenylmethoxycarbonyl)amino]-3,3-dimethylbutanamide

[0372]N-[(1,1-dimethylethoxyl)carbonyl]-N-[2-methylpropyl]-3S-[N¹-(phenylmethoxycarbonyl)amino]-2R-hydroxy-4-phenylbutylaminein ethanol was hydrogenated at 45 psig of hydrogen in the presence of 5%pd(C) catalyst to yieldN-[(1,1-dimethylethoxyl)carbonyl]-N-[2-methylpropyl]-3S-[N¹-(phenylmethoxycarbonyl)amino]-2R-hydroxy-4-phenylbutylamine.Following standard workup, the crude amine (12.24 g, 36.42 mmol) wasadded to a mixture of N-carbobenzyloxycarbonyl-L-tert-leucine (9.67 g,36.42 mmol), HOBT (4.92 g, 36.42 mmol) and EDC (6.98 g, 36.42 mmol) inDMF (300 mL) after the mixture was stirred at room temperature for 1hour. The mixture was stirring for an additional 18 hours. The DMF wasremoved in vacuo, the residue was dissolved in dichloromethane (500 mL),washed with sodium hydroxide (5%, 2×200 mL) and brine (200 mL), driedand concentrated to afford 21 g (quantitative) of the desired product.

[0373] Part C: Preparation of N-[2R-hydroxy-3-[[(1,1-dimethylethoxy)carbonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-amino-3,3-dimethylbutanamide

[0374] N-[2R-hydroxy-3-[[(1,1-dimethylethoxy)carbonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[(phenylmethoxycarbonyl)amino]-3,3-dimethylbutanamide(20 g, 34.29 mmol) in methanol (250 mL) was hydrogenated at roomtemperature in the presence of Pd/C (10%, 5 g). The catalyst wasfiltered off and the filtrate was concentrated to afford 13.8 g (90%) ofthe pure desired product.

EXAMPLE 44

[0375] Preparation of2R-hydroxy-3-{[(1.4-benzodioxan-6-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylCarbamic Acid Phenylmethyl Ester

[0376] To a solution of the N-[3S-[(phenylmethoxycarbonyl)amino]-2R-hydroxy-4-phenylbutyl]-N-(2-methylpropyl)amine (0.5 g, 1.35mmol) in CH₂Cl₂ (5.0 mL) containing Et₃N (0.35 mL, 2.5 mmol) was added1,4-benzodioxan-6-sulfonyl chloride (0.34 g, 1.45 mmol) and stirred at0° C. for 30 min. After stirring at room temperature for 1 hour, thereaction mixture was diluted with CH₂Cl₂ (20 mL), washed with cold 1NHCl (3×20 mL), water (2×20 mL), satd. NaHCO₃ (2×20 mL) and water (3×20mL), dried (Na₂SO₄) and concentrated under reduced pressure. Theresulting residue was purified by flash chromatography using 35% EtOAcin hexane to give the desired product as a white amorphous solid whichcrystallized from MeOH as a white powder (0.65 g. 84% yield): m. p.82-84° C., HRMS-FAB calcd for C₃₀H₃₇N₂O₇S 569.2321 (MH⁺), found569.2323.

EXAMPLE 45

[0377] Preparation of[2R-hydroxy-3-[(benzothiazole-6-sulfonyl)-(2-methyl]propyl)amino]-1S-(phenylmethyl)propylamineHydrochloride

[0378] Part A: Preparation of [2R-hydroxy-3-[(4-aminophenylsulfonyl)(2-methylpropyl]amino]-1S-(phenylmethyl)propylcarbamic Acid t-butylEster

[0379] A mixture of[2R-hydroxy-3-[(4-aminophenylsulfonyl)(2-methylpropyl)-amino]-1S-(phenylmethyl)propylamine3.7 g (9.45 mmol) and BOC-ON (2.33 g, 9.45 mmol) and triethylamine(0.954 g, 9.45 mmol) in tetrahydrofuran (60 mL) was stirred for 16 hoursand concentrated in vacuo. The residue was dissolved in dichloromethane(200 mL), washed with sodium hydroxide (1N, 100 mL) and citric acid (5%,100 mL), dried (MgSO₄), and concentrated to afford 1.18 g (94%) of thedesired product as a white solid.

[0380] Part B: Preparation of[2R-Hydroxy-3-[[(2-aminobenzothiazol-6-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylcarbamicAcid t-butyl Ester

[0381] The[2R-hydroxy-3-[(4-aminophenylsulfonyl)(2-methylpropyl)amino]-1S-(phenylmethyl)propylcarbamicacid t-butyl ester (1.12 g, 2.279 mmol) was added to a well mixed powderof anhydrous copper sulfate (4.48 g) and potassium thiocyanate (5.60 g)followed by dry methanol (35 mL) and the resulting black-brownsuspension was heated at reflux for 2 hours. The reaction mixture turnedgrey. The reaction mixture was filtered and the filtrate was dilutedwith water (50 mL) and heated at reflux. Ethanol was added to thereaction mixture, cooled and filtered. The filtrate upon concentrationafforded a residue which was chromatographed (ethyl acetate:methanol90:10) to afford 0.80 g (78%) of the deprotected compound as a solid.This was directly reprotected via the following procedure; (2.25 g,5.005 mmol) BOC-ON (1.24 g), and triethylamine (0.505 g, 5.005 mmol) intetrahydrofuran (20 mL) was stirred at room temperature for 18 hours.The reaction mixture was concentrated and the residue was dissolved indichloromethane (200 mL) and was washed with sodium hydroxide (1N, 100mL) and citric acid (5%, 100 mL) dried (MgSO₄) and concentrated toafford a residue which was chromatographed (ethyl acetate:hexane 3:1) toafford 1.8 g. (65%) of the desired product as a solid.

[0382] Part C: Preparation of[2R-hydroxy-3-[[(benzothiazol-6-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylcarbamic acid t-butyl Ester

[0383][2R-Hydroxy-3-[[(2-aminobenzothiazol-6-yl)sulfonyl](2-methylpropyl)amino]-is-(phenylmethyl)propylcarbamicacid t-butyl ester (1.80 g, 3.2755 mmol) was added to a solution ofisoamylnitrite (0.88 mL) in dioxane (20 mL) and the mixture was heatedat 85° C. After the cessation of evolution of nitrogen, the reactionmixture was concentrated and the residue was purified by chromatography(hexane:ethyl acetate 1:1) to afford 1.25 g (78%) of the desired productas a solid.

[0384] Part D: Preparation of[2R-hydroxy-3-[[(benzothiazol-6-yl)sulfonyl)(2-methylpropyl)amino]-1S-(phenylmethyl)propylamine.hydrochloride.

[0385][2R-hydroxy-3-[[(benzothiazol-6-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylcarbamic acid t-butyl ester (1.25 g, 2.3385 mmol) was addeddioxane/HCl (4N, 10 mL) and was stirred at room temperature for 2 hoursand concentrated. Excess HCl was chased with toluene to afford 1.0 g(quantitative yield) of the desired product.

EXAMPLE 46

[0386]

[0387] Preparation of2S-amino-N-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]pent-4-ynamide

[0388] Part A. Preparation of2S-[[(1,1-dimethylethoxy)carbonyl]amino]-N-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]pent-4-ynamide

[0389] To a cooled solution of N-t-Boc-L-propargyl glycine (5.0 g, 23.4mmol) and 4.7 g (1.5 equiv.) of N-hydroxybenzotriazole in 40 mL ofN,N-dimethylformamide was added 4.6 g (23.4 mmol) of EDC and stirred at0 C for one hour. To this was added a solution of 12.10 g (23.4 mmol) of2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylaminein 6 mL of N,N-dimethylformamide and the solution stirred for 16 hours.The solvent was removed by rotory evaporation, replaced with ehtylacetate, and washed with saturated sodium bicarbonate, 5% citric acidand brine. The organics were dried over magnesium sulfate, filtered andconcentrated to yield 13.3 grams of crude product, which wascrystallized from diethyl ether: ethyl acetate to yield 6.9 g of2S-[[(1,1-dimethylethoxy)carbonyl]amino]-N-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]pent-4-ynamide.

[0390] Part B. Preparation of2S-amino-N-[2R-hydroxy-3-[[(1,3-benzodioxol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]pent-4-ynamide

[0391] 5.0 g (8.12 mmol) of the product from Part A. was dissolved in 20mL of 4N HCl in dioxane and stirred for 30 minutes. The precipitatedproduct was stripped two times from diethyl ether and this crudehydrochloride salt was used in continuing reactions.

EXAMPLE 47

[0392] Preparation ofN-[2R-hydroxy-3-[[(benzothiazol-6-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-(amino)-3,3-dimethylbutanamide.dihydrobromide

[0393] Part A: Preparation ofN-[2R-hydroxy-3-[[(benzothiazol-6-yl)sulfonyl](2-methylpropyl)-amino]-1S-(phenylmethyl)propyl]-2S-[[(N-benzyloxy)carbonyl]amino]-3,3-dimethylButanamide

[0394] A mixture of N-benzyloxycarbonyl-t-butylglycine (2.0 g, 7.538mmol), HOBT (1.02 g, 7.55 mmol), and EDC (1.45 g, 7.55 mmol) in DMF (20mL) was stirred at room temperature for 1 hour. Then[2R-hydroxy-3-[[(benzothiazol-6-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylamine hydrochloride (3.825 g, 7.54 mmol) and N-methylmorpholine(3.80 g) were added and the stirring continued for 18 hours. The DMF wasremoved in vacuo, the residue was dissolved in dichloromethane (500 mL),and washed with citric acid (1N, 100 mL), sodium bicarbonate (100 mL),brine (200 mL), dried, filtered, and concentrated to afford 4.69 g (91%)of pureN-[2R-hydroxy-3-[[(benzothiazol-6-yl)sulfonyl)(2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[N-(phenylmethoxycarbonyl)amino]-3,3-dimethylbutanamide.

[0395] Part B: Preparation ofN-[2R-hydroxy-3-[[(benzothiazol-6-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-(amino)-3,3-dimethylbutanamide.dihydrobromide

[0396] A solution ofN-[2R-hydroxy-3-[[(benzothiazol-6-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-[N-(phenylmethoxycarbonyl)amino]-3,3-dimethyl butanamide(4.69 g, 6.89 mmol) in dichloroethane (200 mL) was treated with HBr (48%in acetic acid, 7.1 mL), and the reaction mixture was stirred for 2hours at room temperature. The reaction mixture was concentrated and theresidue was washed with diethyl ether several times to afford 4.88 g ofthe desired dihydrobromide product as a powder: high resolution FAB-MSCalcd for C₂₇H₃₈N₄O₄S₂: 547.2413, found: 547.2429 (M+H).

EXAMPLE 48

[0397] Preparation of 5-chlorosulfonyl-2-carbomethoxyamino-benzimidazole

[0398] A solution of 2-carbomethoxyamino-benzimidazole (5.0 g, 0.026mole) in chlorosulfonic acid (35.00 mL) was stirred at 0° C. for 30minutes and at room temperature for 3 hours. The resulting dark coloredreaction mixture was poured into an ice-water mixture (200 mL), andstirred at room temperature for 30 minutes. The resulting precipitatewas filtered and washed with cold water (500 mL). The solid was driedovernight under high vacuum in a desiccator over NaOH pellets to give5-chlorosulfonyl-2-carbomethoxyamino-benzimidazole (5.9 g, 78%) as agrey powder. ¹H NMR (DMSO-d₆) d: 3.89 (s, 3H), 7.55 (d, J=8.4 Hz, 1H),7.65 (d, J=8.4 Hz, 1H), 7.88 (s, 1H) (German Patent DE 3826036)

EXAMPLE 49

[0399] Preparation ofN-[2R-hydroxy-3-[N¹-[(2-carbomethoxyamino-benzimidazol-5-yl)sulfonyl]-N¹-(2-methylpropyl)amino]-1S-(phenylmethyl)propyl]carbamicAcid Phenylmethyl Ester

[0400] To a cold solution of N-[3S-[(phenylmethoxycarbonyl)amino]-2R-hydroxy-4-phenylbutyl]-N-(2-methylpropyl)amine (5.0 g, 13.5mmol) in dichloromethane (70 mL) was added triethylamine (5.95 g, 54.0mmol) followed by the addition of5-chlorosulfonyl-2-carbomethoxyamino-benzimidazole (4.29 g, 14.85 mmol)in small portions as a solid. The reaction mixture was stirred at 0° C.for 30 minutes and at room temperature for 2.5 hours when reaction ofthe amino alcohol was complete. The mixture was cooled and filtered, andthe filtrate was concentrated. The resulting residue was dissolved inEtOAc (200 mL), washed successively with cold 5% citric acid (3×50 mL),saturated aqueous sodium bicarbonate (3×50 mL) and water (3×100 mL),then dried (Na₂SO₄), concentrated and dried under vacuum. The residuewas triturated with methanol, cooled, filtered, washed with MeOH-EtOAc(1:1, v/v) and dried in a desiccator to give pureN-[2R-hydroxy-3-[[(2-carbomethoxyamino-benzimidazol-5-yl)sulfonyl](2-methylpropyl)-amino]-1S-(phenylmethyl) propyl]carbamic acidphenylmethyl ester (6.02 g, 72%) as a light brown powder: FABMS: m/z=630(M+Li); HRMS: calcd. for C₃₁H₃₈N₅O₇S (M+H) 624.2492, found 624.2488.

EXAMPLE 50

[0401] Preparation of 2R-hydroxy-3-[[(2-amino-benzimidazol-5-yl)sulfonyl](2-methyl-propyl)amino]-1S-(phenylmethyl)propylamine

[0402] A solution ofN-[2R-hydroxy-3-[[(2-carbomethoxyamino-benzimidazol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]carbamicacid phenylmethyl ester (0.36 g, 0.58 mmol) in 2.5 N methanolic KOH(2.00 mL) was heated at 70° C. under a nitrogen atmosphere for 3 hours.The reaction mixture was diluted with water (10 mL) and extracted withEtOAc (3×15 mL). The combined organic extracts were washed with brine,dried (Na₂SO₄) and concentrated. The resulting residue was purified byreverse-phase HPLC using a 10-90% CH₃CN/H₂O gradient (30 min) at a flowrate of 70 mL/min. The appropriate fractions were combined and freezedried to give pure2R-hydroxy-3-[[(2-amino-benzimidazol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenyl-methyl)propylamine(0.22 g, 58%) as a white powder: FAB-MS m/z=432 (M+H); HRMS: calcd. forC₂₁H₃₀N₅O₃S (M+H) 432.2069, found 432.2071.

EXAMPLE 51

[0403] Preparation ofN-[2R-hydroxy-3-[[(2-amino-benzimidazol-5-yl)sulfonyl](2-methylpropyl)-amino]-1S-(phenylmethyl)propyl]carbamicAcid Phenylmethyl Ester

[0404] To a solution of2R-hydroxy-3-[[(2-amino-benzimidazol-5-yl)sulfonyl](2-methyl-propyl)amino]-1S-(phenylmethyl)propylamine (0.22 g, 0.33 mmol) in THF (3.00 mL), triethylamine (0.11 g,1.1 mmol) and benzyloxycarbonyl succinimide (0.09 g, 0.36 mmol) wereadded, and the reaction mixture was stirred at room temperature for 16hours. The solution was concentrated, and the residue was partitionedbetween EtOAc (15 mL) and saturated aqueous sodium bicarbonate. Theorganic phase was washed with brine, dried (Na₂SO₄), and concentrated.The resulting residue was purified by reverse-phase HPLC using a 10-90%CH₃CN/H₂O gradient (30 min) at a flow rate of 70 mL/min. The appropriatefractions were combined and freeze dried to give pureN-[2R-hydroxy-3-[[(2-amino-benzimidazol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]carbamicacid phenylmethyl ester (0.12 g, 61%) as a white powder: FAB-MS m/z=566(M+H);

[0405] HRMS: calcd. for C₂₉H₃₆N₅O₅s 566.2437 (M+H), found 566.2434.

EXAMPLE 52

[0406] Preparation of2R-hydroxy-3-[[(2-carbomethoxyamino-benzimidazol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylamine

[0407] A solution ofN-[2R-hydroxy-3-[[(2-carbomethoxyamino-benzimidazole-5-yl)sulfonyl](2-methylpropyl)-amino]-1S-(phenylmethyl)propyl]carbamicacid phenylmethyl ester (2.5 g, 0.4 mmol) in MeOH (10 mL) and THF (50mL) was hydrogenated in the presence of 10% Pd/C (1.2 g) at roomtemperature at 60 psi for 16. hours. The catalyst was removed byfiltration, and the filtrate was concentrated under reduced pressure.The resulting residue was triturated with ether and filtered. The solidsubstance thus obtained was washed with ether and dried in vacuo toafford pure2R-hydroxy-3-[[(2-carbomethoxyamino-benzimidazol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylamine(1.5 g, 77%) as an off white powder: R_(t)=12.8 min; FAB-MS m/z=490(M+H); HRMS: calcd. for C₂₃H₃₂N₅O₅S 490.2124 (M+H), found 490.2142.

EXAMPLE 53

[0408] Preparation ofN-[2R-hydroxy-3-[[(2-carbomethoxyamino-benzimidazol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-amino-3.3-dimethylbutanamide

[0409] Part A: Preparation ofN-[2R-hydroxy-3-[N¹-[(2-carbomethoxyamino-benzimidazol-5-yl)sulfonyl]-N¹-(2-methylpropyl)amino]-1S-(phenylmethyl)propyl-2S-[(phenylmethoxy-carbonyl)amino]-3,3-dimethylbutanamide

[0410] To a solution of N-carbobenzyloxycarbonyl-L-tert-leucine (0.65 g,2.45 mmol) in DMF (10 mL) was added HOBt (0.5 g, 3.22 mmol) and EDC(0.49 g, 2.55 mmol), and the resulting mixture was stirred at 0° C. for2 hours. Then a solution of2R-hydroxy-3-[[(2-carbomethoxyamino-benzimidazol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propylamine(1.2 g, 2.45 mmol) in DMF (4 mL) and N-methyl morpholine (0.74 g, 7.3mmol) was added, and the mixture was stirred at room temperature for 16hours. The DMF was then distilled away in vacuo, and the remainingresidue was partitioned between cold 1N aqueous HCl (100 mL) and EtOAc(200 mL). The organic phase was washed successively with cold 1N HCl(2×50 mL), brine (2×50 mL), 0.25 N NaOH (3×50 mL), brine, dried (Na₂SO₄)and concentrated in vacuo. The resulting residue was purified by silicagel flash column chromatography using EtOAc as the eluent to afford 1.5g (83%) of pureN-[2R-hydroxy-3-[[(2-carbomethoxyamino-benzimidazol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl-2S-[(phenylmethoxy-carbonyl)amino]-3,3-dimethylbutanamide: R_(t)=21.2 min; FAB-MS m/z=737 (M+H), HRMS: calcd. forC₃₇H₄₉N₆O₈S 737.3333 (M+H), found 737.3334.

[0411] Part B: Preparation ofN-[2R-hydroxy-3-[[(2-carbomethoxyamino-benzimidazol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-amino-3,3-dimethylbutanamide

[0412] A solution ofN-[2R-hydroxy-3-[[(2-carbomethoxyamino-benzimidazol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl-2S-[(phenylmethoxycarbonyl)amino]-3,3-dimethylbutanamide(4.0 g, 5.4 mmol) in MeOH (15 mL) and THF (65 mL) was hydrogenated inthe presence of 10% Pd/C (2.0 g) at room temperature at 50 psi for 16hours. The catalyst was removed by filtration, and the filtrate wasconcentrated under reduced pressure. The resulting residue wastriturated with ether and filtered. The solid residue was washed withether and dried in vacuo to affordN-[2R-hydroxy-3-[[(2-carbomethoxyamino-benzimidazol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl]-2S-amino-3,3-dimethylbutanamide(2.9 g, 88%) as a pale yellow powder. A portion of the material waspurified by reverse-phase HPLC using a 10-90% CH₃CN/H₂O gradient (30min) at a flow rate of 70 mL/min. The appropriate fractions werecombined and freeze dried to give pureN-[2R-hydroxy-3-[[(2-carbomethoxyamino-benzimidazol-5-yl)sulfonyl](2-methylpropyl)amino]-1S-(phenylmethyl)propyl-2S-amino-3,3-dimethylbutanamideas a white powder: R_(t)=13.9 min; FAB-MS m/z=609 (M+Li), 603 (M+H);HRMS: calcd. for C₂₉H₄₃N₆O₆S 603.2965 (M+H), found 603.2972.

EXAMPLE 54

[0413] Following the procedures of the previous Examples, the compoundsset forth in Tables 2 through 9 can be prepared. TABLE 2

Entry R³ R⁴ 1 isobutyl 4-aminophenyl 2 isobutyl 3-aminophenyl 3cyclopentylmethyl phenyl 4 cyclohexylmethyl phenyl 5 cyclopentylmethyl1,3-benzodioxol-5-yl 6 cyclohexylmethyl 1,3-benzodioxol-5-yl 7cyclopentylmethyl benzofuran-5-yl 8 cyclohexylmethyl benzofuran-5-yl 9cyclopentylmethyl 2,3-dihydrobenzofuran-5-yl 10 cyclohexylmethyl2,3-dihydrobenzofuran-5-yl 11 isobutyl 1,3-benzodioxol-5-yl 12 isobutylbenzofuran-5-yl 13 isobutyl 2,3-dihydrobenzofuran-5-yl 14 isobutyl1,4-benzodioxan-6-yl 15 isoamyl 1,3-benzodioxol-5-yl 16 isoamyl2,3-dihydrobenzofuran-5-yl 17 isoamyl 1,4-benzodioxan-6-yl 18 isobutylbenzothiazol-6-yl 19 isobutyl 2-amino-benzothiazol-6-yl 20 isobutylbenzoxazol-5-yl 21 cyclopentylmethyl 4-methoxyphenyl 22 cyclohexylmethyl4-methoxyphenyl

[0414] TABLE 3A

Entry A

[0415] TABLE 3B

Entry A

[0416] TABLE 3C

Entry A

[0417] TABLE 3D

Entry A

[0418] TABLE 3E

Entry A

[0419] TABLE 4A

Entry R² (CH₃)₂CHCH₂— (4-FC₆H₅)CH₂— CH₃CH₂CH₂CH₂— (naphth-2-yl)CH₂—CH₃SCH₂CH₂— C₆H₁₁CH₂— C₆H₅CH₂— C₆H₅SCH₂— (4-CH₃OC₆H₅)CH₂—(naphth-2-yl)SCH₂—

[0420] TABLE 4B

Entry R² (CH₃)₂CHCH₂— (4-FC₆H₅)CH₂— CH₃CH₂CH₂CH₂— (naphth-2-yl)CH₂—CH₃SCH₂CH₂— C₆H₁₁CH₂— C₆H₅CH₂— C₆H₅SCH₂— (4-CH₃OC₆H₅)CH₂—(naphth-2-yl)SCH₂—

[0421] TABLE 4C

Entry R² (CH₃)₂CHCH₂— (4-FC₆H₅)CH₂— CH₃CH₂CH₂CH₂— (naphth-2-yl)CH₂—CH₃SCH₂CH₂— C₆H₁₁CH₂— C₆H₅CH₂— C₆H₅SCH₂— (4-CH₃OC₆H₅)CH₂—(naphth-2-yl)SCH₂—

[0422] TABLE 4D

Entry R² (CH₃)₂CHCH₂— (4-FC₆H₅)CH₂— CH₃CH₂CH₂CH₂— (naphth-2-yl)CH₂—CH₃SCH₂CH₂— C₆H₁₁CH₂— C₆H₅CH₂— C₆H₅SCH₂— (4-CH₃OC₆H₅)CH₂—(naphth-2-yl)SCH₂—

[0423] TABLE 5A

Entry R³ —CH₂CH₂CH₃—CH₂CH₂CH₂CH₃—CH₂CH(CH₃)₂—CH₂CH₂CH(CH₃)₂

[0424] TABLE 5B

Entry R³ —CH₂CH₂CH₂CH₃—CH₂CH₂CH₃—CH₂CH(CH₃)₂—CH₂CH₂CH(CH₃)₂

[0425] TABLE 5C

Entry R³ —CH₂CH₂CH₃—CH₂CH₂CH₂CH₃—CH₂CH(CH₃)₂—CH₂CH₂CH(CH₃)₂

[0426] TABLE 5D

Entry R³ —CH₂CH₂CH₂CH_(3 —CH) ₂CH₂CH₃—CH₂CH(CH₃)₂—CH₂CH₂CH(CH₃)₂

[0427] TABLE 6A

Entry R¹

[0428] TABLE 6B

Entry R¹

[0429] TABLE 6C

Entry R¹

[0430] TABLE 6D

Entry R¹ 8

[0431] TABLE 6E

Entry R¹

[0432] TABLE 7A

Entry R⁴

[0433] TABLE 7B

Entry R⁴

[0434] TABLE 7C

Entry R⁴

[0435] TABLE 7D

Entry R⁴

[0436] TABLE 7E

Entry R⁴

[0437] TABLE 7F

Entry R⁴

[0438] TABLE 8A

Entry R⁴

[0439] TABLE 8B

Entry R⁴

[0440] TABLE 8C

Entry R⁴

[0441] TABLE 8D

Entry R⁴

[0442] TABLE 8E

Entry R⁴

[0443] TABLE 8F

Entry R⁴

[0444] TABLE 9A

Entry R⁴

[0445] TABLE 9B

Entry R⁴

[0446] TABLE 9C

Entry R⁴

[0447] TABLE 9D

Entry R⁴

[0448] TABLE 9E

Entry R⁴

[0449] TABLE 9F

Entry R⁴

EXAMPLE 55

[0450] The compounds of the present invention are effective HIV proteaseinhibitors. Utilizing an enzyme assay as described below, the compoundsset forth in the examples herein disclosed inhibited the HIV enzyme. Thepreferred compounds of the present invention and their calculated IC₅₀(inhibiting concentration 50%, i.e., the concentration at which theinhibitor compound reduces enzyme activity by 50%) values are shown inTable 10. The enzyme method is described below. The substrate is2-Ile-Nle-Phe(p-NO₂)-Gln-ArgNH₂. The positive control is MVT-101(Miller, M. et al, Science, 246, 1149 (1989)]

[0451] The assay conditions are as follows:

[0452] Assay buffer:

[0453] 0.20 mM sodium phosphate, pH 6.4

[0454] 20% glycerol

[0455] 1 mM EDTA

[0456] 1 mM DTT

[0457] 0.1% CHAPS

[0458] The above described substrate is dissolved in DMSO, then diluted10 fold in assay buffer. Final substrate concentration in the assay is80 μM. HIV protease is diluted in the assay buffer to a final enzymeconcentration of 12.3 nanomolar, based on a molecular weight of 10,780.

[0459] The final concentration of DMSO is 14% and the finalconcentration of glycerol is 18%. The test compound is dissolved in DMSOand diluted in DMSO to 10× the test concentration; 10 μl of the enzymepreparation is added, the materials mixed and then the mixture isincubated at ambient temperature for 15 minutes. The enzyme reaction isinitiated by the addition of 40 μl of substrate. The increase influorescence is monitored at 4 time points (0, 8, 16 and 24 minutes) atambient temperature. Each assay is carried out in duplicate wells.

[0460] The preceding examples can be repeated with similar success bysubstituting the generically or specifically described reactants and/oroperating conditions of this invention for those used in the precedingexamples.

EXAMPLE 56

[0461] The effectiveness of various compounds were determined in theabove-described enzyme assay and in a CEM cell assay.

[0462] The HIV inhibition assay method of acutely infected cells is anautomated tetrazolium based calorimetric assay essentially that reportedby Pauwles et al, J. Virol. Methods, 20, 309-321 (1988). Assays wereperformed in 96-well tissue culture plates. CEM cells, a CD4⁺ cell line,were grown in RPMI-1640 medium (Gibco) supplemented with a 10% fetalcalf serum and were then treated with polybrene (2 μg/ml). An 80 μlvolume of medium containing 1×10⁴ cells was dispensed into each well ofthe tissue culture plate. To each well was added a 100 μl volume of testcompound dissolved in tissue culture medium (or medium without testcompound as a control) to achieve the desired final concentration andthe cells were incubated at 37° C. for 1 hour. A frozen culture of HIV-1was diluted in culture medium to a concentration of 5×10⁴ TCID₅₀ per ml(TCID₅₀=the dose of virus that infects 50% of cells in tissue culture),and a 20 μL volume of the virus sample (containing 1000 TCID₅₀ of virus)was added to wells containing test compound and to wells containing onlymedium (infected control cells). Several wells received culture mediumwithout virus (uninfected control cells). Likewise, the intrinsictoxicity of the test compound was determined by adding medium withoutvirus to several wells containing test compound. In summary, the tissueculture plates contained the following experiments: Cells DrugVirus 1. + − − 2. + + − 3. + − + 4. + + +

[0463] In experiments 2 and 4 the final concentrations of test compoundswere 1, 10, 100 and 500 μg/ml. Either azidothymidine (AZT) ordideoxyinosine (ddI) was included as a positive drug control. Testcompounds were dissolved in DMSO and diluted into tissue culture mediumso that the final DMSO concentration did not exceed 1.5% in any case.DMSO was added to all control wells at an appropriate concentration.

[0464] Following the addition of virus, cells were incubated at 37° C.in a humidified, 5% CO₂ atmosphere for 7 days. Test compounds could beadded on days 0, 2 and 5 if desired. On day 7, post-infection, the cellsin each well were resuspended and a 100 μl sample of each cellsuspension was removed for assay. A 20 μL volume of a 5 mg/ml solutionof 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)was added to each 100 μL cell suspension, and the cells were incubatedfor 4 hours at 27° C. in a 5% CO₂ environment. During this incubation,MTT is metabolically reduced by living cells resulting in the productionin the cell of a colored formazan product. To each sample was added 100μl of 10% sodium dodecylsulfate in 0.01 N HCl to lyse the cells, andsamples were incubated overnight. The absorbance at 590 nm wasdetermined for each sample using a Molecular Devices microplate reader.Absorbance values for each set of wells is compared to assess viralcontrol infection, uninfected control cell response as well as testcompound by cytotoxicity and antiviral efficacy. TABLE 10 IC₅₀ EC₅₀Entry Compound (nM) (nM) 1

2 12 2

3

[0465] The compounds of the present invention are effective antiviralcompounds and, in particular, are effective retroviral inhibitors asshown above. Thus, the subject compounds are effective HIV proteaseinhibitors. It is contemplated that the subject compounds will alsoinhibit other retroviruses such as other lentiviruses in particularother strains of HIV, e.g. HIV-2, human T-cell leukemia virus,respiratory syncitial virus, simia immunodeficiency virus, felineleukemia virus, feline immuno-deficiency virus, hepadnavirus,cytomegalovirus and picornavirus. Thus, the subject compounds areeffective in the treatment, proplylaxis of retroviral infections and/orthe prevention of the spread of retroviral infections.

[0466] The subject compounds are also effective in preventing the growthof retroviruses in a solution. Both human and animal cell cultures, suchas T-lymphocyte cultures, are utilized for a variety of well knownpurposes, such as research and diagnostic procedures includingcalibrators and controls. Prior to and during the growth and storage ofa cell culture, the subject compounds may be added to the cell culturemedium at an effective concentration to prevent the unexpected orundesired replication of a retrovirus that may inadvertently,unknowingly or knowingly be present in the cell culture. The virus maybe present originally in the cell culture, for example HIV is known tobe present in human T-lymphocytes long before it is detectable in blood,or through exposure to the virus. This use of the subject compoundsprevents the unknowing or inadvertent exposure of a potentially lethalretrovirus to a researcher or clinician.

[0467] Compounds of the present invention can possess one or moreasymmetric carbon atoms and are thus capable of existing in the form ofoptical isomers as well as in the form of racemic or nonracemic mixturesthereof. The optical isomers can be obtained by resolution of theracemic mixtures according to conventional processes, for example byformation of diastereoisomeric salts by treatment with an opticallyactive acid or base. Examples of appropriate acids are tartaric,diacetyltartaric, dibenzoyltartaric, ditoluoyltartaric andcamphorsulfonic acid and then separation of the mixture ofdiastereoisomers by crystallization followed by liberation of theoptically active bases from these salts. A different process forseparation of optical isomers involves the use of a chiralchromatography column optimally chosen to maximize the separation of theenantiomers. Still another available method involves synthesis ofcovalent diastereoisomeric molecules by reacting compounds of Formula Iwith an optically pure acid in an activated form or an optically pureisocyanate. The synthesized diastereoisomers can be separated byconventional means such as chromatography, distillation, crystallizationor sublimation, and then hydrolyzed to deliver the enantiomerically purecompound.

[0468] The optically active compounds of Formula I can likewise beobtained by utilizing optically active starting materials. These isomersmay be in the form of a free acid, a free base, an ester or a salt. Thecompounds of the present invention can be used in the form of saltsderived from inorganic or organic acids. These salts include but are notlimited to the following: acetate, adipate, alginate, citrate,aspartate, benzoate, benzenesulfonate, bisulfate, butyrate, camphorate,camphorsulfonate, digluconate, cyclopentanepropionate, dodecylsulfate,ethanesulfonate, glucoheptanoate, glycerophosphate, hemisulfate,heptanoate, hexanoate, fumarate, hydrochloride, hydrobromide,hydroiodide, 2-hydroxy-ethanesulfonate, lactate, maleate,methanesulfonate, nicotinate, 2-naphthalenesulfonate, oxalate, palmoate,pectinate, persulfate, 3-phenylpropionate, picrate, pivalate,propionate, succinate, tartrate, thiocyanate, tosylate, mesylate andundecanoate. Also, the basic nitrogen-containing groups can bequaternized with such agents as lower alkyl halides, such as methyl,ethyl, propyl, and butyl chloride, bromides, and iodides; dialkylsulfates like dimethyl, diethyl, dibutyl, and diamyl sulfates, longchain halides such as decyl, lauryl, myristyl and stearyl chlorides,bromides and iodides, aralkyl halides like benzyl and phenethylbromides, and others. Water or oil-soluble or dispersible products arethereby obtained.

[0469] Examples of acids which may be employed to form pharmaceuticallyacceptable acid addition salts include such inorganic acids ashydrochloric acid, sulphuric acid and phosphoric acid and such organicacids as oxalic acid, maleic acid, succinic acid and citric acid. Otherexamples include salts with alkali metals or alkaline earth metals, suchas sodium, potassium, calcium or magnesium or with organic bases.

[0470] Total daily dose administered to a host in single or divideddoses may be in amounts, for example, from 0.001 to 10 mg/kg body weightdaily and more usually 0.01 to 1 mg. Dosage unit compositions maycontain such amounts of submultiples thereof to make up the daily dose.

[0471] The amount of active ingredient that may be combined with thecarrier materials to produce a single dosage form will vary dependingupon the host treated and the particular mode of administration.

[0472] The dosage regimen for treating a disease condition with thecompounds and/or compositions of this invention is selected inaccordance with a variety of factors, including the type, age, weight,sex, diet and medical condition of the patient, the severity of thedisease, the route of administration, pharmacological considerationssuch as the activity, efficacy, pharmacokinetic and toxicology profilesof the particular compound employed, whether a drug delivery system isutilized and whether the compound is administered as part of a drugcombination. Thus, the dosage regimen actually employed may vary widelyand therefore may deviate from the preferred dosage regimen set forthabove.

[0473] The compounds of the present invention may be administeredorally, parenterally, by inhalation spray, rectally, or topically indosage unit formulations containing conventional nontoxicpharmaceutically acceptable carriers, adjuvants, and vehicles asdesired.

[0474] Topical administration may also involve the use of transdermaladministration such as transdermal patches or iontophoresis devices. Theterm parenteral as used herein includes subcutaneous injections,intravenous, intramuscular, intrasternal injection, or infusiontechniques.

[0475] Injectable preparations, for example, sterile injectable aqueousor oleaginous suspensions may be formulated according to the known artusing suitable dispersing or wetting agents and suspending agents. Thesterile injectable preparation may also be a sterile injectable solutionor suspension in a nontoxic parenterally acceptable diluent or solvent,for example, as a solution in 1,3-butanediol. Among the acceptablevehicles and solvents that may be employed are water, Ringer's solution,and isotonic sodium chloride solution. In addition, sterile, fixed oilsare conventionally employed as a solvent or suspending medium. For thispurpose any bland fixed oil may be employed including synthetic mono- ordiglycerides. In addition, fatty acids such as oleic acid find use inthe preparation of injectables.

[0476] Suppositories for rectal administration of the drug can beprepared by mixing the drug with a suitable nonirritating excipient suchas cocoa butter and polyethylene glycols which are solid at ordinarytemperatures but liquid at the rectal temperature and will thereforemelt in the rectum and release the drug.

[0477] Solid dosage forms for oral administration may include capsules,tablets, pills, powders, and granules. In such solid dosage forms, theactive compound may be admixed with at least one inert diluent such assucrose lactose or starch. Such dosage forms may also comprise, as innormal practice, additional substances other than inert diluents, e.g.,lubricating agents such as magnesium stearate. In the case of capsules,tablets, and pills, the dosage forms may also comprise buffering agents.Tablets and pills can additionally be prepared with enteric coatings.

[0478] Liquid dosage forms for oral administration may includepharmaceutically acceptable emulsions, solutions, suspensions, syrups,and elixirs containing inert diluents commonly used in the art, such aswater. Such compositions may also comprise adjuvants, such as wettingagents, emulsifying and suspending agents, and sweetening, flavoring,and perfuming agents.

[0479] While the compounds of the invention can be administered as thesole active pharmaceutical agent, they can also be used in combinationwith one or more immunomodulators, antiviral agents or otherantiinfective agents. For example, the compounds of the invention can beadministered in combination with AZT, DDI, DDC or with glucosidaseinhibitors, such as N-butyl-1-deoxynojirimycin or prodrugs thereof, forthe prophylaxis and/or treatment of AIDS. When administered as acombination, the therapeutic agents can be formulated as separatecompositions which are given at the same time or different times, or thetherapeutic agents can be given as a single composition.

[0480] The foregoing is merely illustrative of the invention and is notintended to limit the invention to the disclosed compounds. Variationsand changes which are obvious to one skilled in the art are intended tobe within the scope and nature of the invention which are defined in theappended claims.

[0481] From the foregoing description, one skilled in the art can easilyascertain the essential characteristics of this invention, and withoutdeparting from the spirit and scope thereof, can make various changesand modifications of the invention to adapt it to various usages andconditions.

1. A compound represented by the formula:

or a pharmaceutically acceptable salt, prodrug or ester thereof, whereinn represents 0 or 1; R¹ represents alkyl of 1-5 carbon atoms, alkenyl of2-5 carbon atoms, alkynyl of 2-5 carbon atoms, hydroxyalkyl of 1-3carbon atoms, alkoxyalkyl of 1-3 alkyl carbon atoms and 1-3 alkoxycarbon atoms, cyanoalkyl of 1-3 alkyl carbon atoms, imidazolylmethyl,—CH₂CONH₂, —CH₂CH₂CONH₂, —CH₂S(O)₂NH₂, —CH₂SCH₃, —CH₂S(O)CH₃,—CH₂S(O)₂CH₃, —C(CH₃)₂SCH₃, —C(CH₃)₂S(O)CH₃ or —C(CH₃)₂S(O)₂CH₃; R³represents alkyl of 1-5 carbon atoms, cycloalkyl of 5-8 ring members orcycloalkylmethyl of 3-6 ring members; R⁴ represents aryl, benzo fused 5to 6 ring member heteroaryl or benzo fused 5 to 6 ring memberheterocyclo radicals; or a radical of the formula

wherein A and B each independently represent O, S, SO or SO₂; R⁶represents deuterium, alkyl of 1-5 carbon atoms, fluoro or chloro; R⁷represents hydrogen, deuterium, methyl, fluoro or chloro; or a radicalof the formula

wherein Z represents O, S or NH; and R⁹ represents a radical of formula

wherein Y represents O, S or NH; X represents a bond, O or NR²¹; R²⁰represents a hydrogen radical, alkyl of 1 to 5 carbon atoms, alkenyl of2 to 5 carbon atoms, alkynyl of 2 to 5 carbon atoms, aralkyl of 1 to 5alkyl carbon atoms, heteroaralkyl of 5 to 6 ring members and 1 to 5alkyl carbon atoms, heterocycloalkyl of 5 to 6 ring members and 1 to 5alkyl carbon atoms, aminoalkyl of 2 to 5 carbon atoms,N-mono-substituted or N,N-disubstituted aminoalkyl of 2 to 5 alkylcarbon atoms wherein said substituents are alkyl of 1 to 3 carbon atoms,aralkyl of 1 to 3 alkyl carbon atoms, carboxyalkyl of 1 to 5 carbonatoms, alkoxycarbonalklkyl of 1 to 5 alkyl carbon atoms, cyanoalkyl of 1to 5 carbon atoms or hydroxyalkyl of 2 to 5 carbon atoms; R²¹ representsa hydrogen radical or alkyl of 1 to 3 carbon atoms; or the radical offormula —NR²⁰R²¹ represents a 5 to 6 ring member heterocyclo radical;and R²² represents alkyl of 1 to 3 carbon atoms or an —R²⁰R²¹N-alkylradical of 1 to 3 alkyl carbon atoms; R¹⁰ represents a hydrogen radical,alkyl of 1-3 carbon atoms, benzyl, phenylmethoxycarbonyl,tert-butoxycarbonyl or (4-methoxyphenylmethoxy)carbonyl radicals; R¹¹represents a hydrogen radical, hydroxyalkyl of 1-3 carbon atoms oralkoxyalkyl, of 1-3 alkyl carbon atoms; and R¹² and R¹³ eachindependently represent a hydrogen radical, hydroxy, alkoxy of 1-3carbon atoms, 2-hydroxyethoxy, hydroxyalkyl of 1-3 carbon atoms oralkoxyalkyl of 1-3 alkyl carbon atoms; or R¹¹ and R¹² or R¹² and R¹³along with the carbon atoms to which they are attached represent a benzoradical, which is optionally substituted with at least one hydroxy oralkoxy radical of 1-3 carbon atoms.
 2. The compound of claim 1, or apharmaceutically acceptable salt, prodrug or ester thereof, wherein R¹represents alkyl of 1-4 carbon atoms, alkenyl of 2-3 carbon atoms,alkynyl of 3-4 carbon atoms, cyanomethyl, imidazolylmethyl, —CH₂CONH₂,—CH₂CH₂CONH₂, —CH₂S(O)₂NH₂, —CH₂SCH₃, —CH₂S(O)CH₃, —CH₂S(O)₂CH₃,—C(CH₃)₂SCH₃, —C(CH₃)₂S(O)CH₃ or —C(CH₃)₂S(O)₂CH₃; R³ represents alkylof 1-5 carbon atoms, cycloalkylmethyl of 3-6 ring members, cyclohexyl orcycloheptyl; R⁴ represents phenyl, 2-naphthyl, 4-methoxyphenyl,4-hydroxyphenyl, 3,4-dimethoxyphenyl, 3-aminophenyl, 4-aminophenyl,2-amino-benzothiazol-5-yl, 2-amino-benzothiazol-6-yl, benzothiazol-5-yl,benzothiazol-6-yl, benzoxazol-5-yl, 2,3-dihydrobenzofuran-5-yl,benzofuran-5-yl, 1,3-benzodioxol-5-yl or 1,4-benzodioxan-6-yl radicals,or a radical of the formula

wherein A and B each represent O; R⁶ represents deuterium, methyl,ethyl, propyl, isopropyl or fluoro; and R⁷ represents hydrogen,deuterium, methyl or fluoro; or a radical of the formula

wherein Z represents O, S or NH; and R⁹ represents a radical of formula

wherein Y represents O, S or NH; X represents a bond, O or NR²¹; R²⁰represents a hydrogen radical, alkyl of 1 to 5 carbon atoms, phenylalkylof 1 to 3 alkyl carbon atoms, heterocycloalkyl of 5 to 6 ring membersand 1 to 3 alkyl carbon atoms, or N-mono-substituted orN,N-disubstituted aminoalkyl of 2 to 3 alkyl carbon atoms wherein saidsubstituents are alkyl of 1 to 3 carbon atoms; R²¹ represents a hydrogenradical or methyl; or the radical of formula —NR²⁰R²¹ representspyrrolidinyl, piperidinyl, piperazinyl, 4-methylpiperazinyl,4-benzylpiperazinyl, morpholinyl or thiamorpholinyl; and R²² representsalkyl of 1 to 3 carbon atoms.
 3. The compound of claim 2, or apharmaceutically acceptable salt, prodrug or ester thereof, wherein n is0; R¹ represents iso-propyl, sec-butyl, tert-butyl, 3-propynyl,imidazolylmethyl, —CH₂CONH₂, —CH₂SCH₃, —CH₂S(O)CH₃, —CH₂S(O)₂CH₃,—C(CH₃)₂SCH₃, —C(CH₃)₂S(O)CH₃ or —C(CH₃)₂S(O)₂CH₃; R³ represents propyl,isoamyl, isobutyl, butyl, cyclohexyl, cycloheptyl, cyclopentylmethyl orcyclohexylmethyl; R⁴ represents phenyl, 2-naphthyl, 4-methoxyphenyl,4-hydroxyphenyl, benzothiazol-5-yl, benzothiazol-6-yl, benzoxazol-5-yl,2,3-dihydrobenzofuran-5-yl, benzofuran-5-yl, 1,3-benzodioxol-5-yl,2-methyl-1,3-benzodioxol-5-yl, 2,2-dimethyl-1,3-benzodioxol-5-yl,2,2-dideutero-1,3-benzodioxol-5-yl, 2,2-difluoro-1,3-benzodioxol-5-yl or1,4-benzodioxan-6-yl radicals; or a radical of the formula

wherein Z represents O, S or NH; and R⁹ represents a radical of formula

wherein Y represents O, S or NH; X represents a bond, O or NR²¹; R²⁰represents a hydrogen radical, methyl, ethyl, propyl, isopropyl,isobutyl, benzyl, 2-(1-pyrrolidinyl)ethyl, 2-(1-piperidinyl)ethyl,2-(1-piperazinyl)ethyl, 2-(4-methylpiperazin-1-yl)ethyl,2-(1-morpholinyl)ethyl, 2-(1-thiamorpholinyl)ethyl or2-(N,N-dimethylamino)ethyl; R²¹ represents a hydrogen radical; and R²²represents methyl; R¹⁰ represents a hydrogen radical, methyl or benzyl;R¹¹ represents a hydrogen radical; and R¹² and R¹³ each independentlyrepresent a hydrogen radical, hydroxy or methoxy; or R¹¹ and R¹² alongwith the carbon atoms to which they are attached represent a benzoradical, which is optionally substituted with at least one hydroxy ormethoxy.
 4. The compound of claim 3 or a pharmaceutically acceptablesalt, ester, or prodrug thereof, wherein R¹ represents sec-butyl,tert-butyl, iso-propyl, 3-propynyl or —C(CH₃)₂S(O)₂CH₃; R⁴ representsphenyl, 4-methoxyphenyl, 4-hydroxyphenyl, benzothiazol-5-yl,benzothiazol-6-yl, 2,3-dihydrobenzofuran-5-yl, benzofuran-5-yl,1,3-benzodioxol-5-yl, 2-methyl-1,3-benzodioxol-5-yl,2,2-dimethyl-1,3-benzodioxol-5-yl, 2,2-dideutero-1,3-benzodioxol-5-yl,2,2-difluoro-1,3-benzodioxol-5-yl, 1,4-benzodioxan-6-yl,2-(methoxycarbonylamino)benzothiazol-6-yl or2-(methoxycarbonylamino)benzimidazol-5-yl; R¹⁰ represents a hydrogenradical or methyl; R¹² represents a hydrogen radical or hydroxy; and R¹³represents a hydrogen radical.
 5. The Compound of claim 1 wherein saidpharmaceutically acceptable salt is hydrochloric acid salt, sulphuricacid salt, phosphoric acid salt, oxalic acid salt, maleic acid salt,succinic acid salt, citric acid salt or methanesulfonic acid salt. 6.The compound of claim 5 wherein said pharmaceutically acceptable salt ishydrochloric acid salt, oxalic acid salt, citric acid salt ormethanesulfonic acid salt. 7 (canceled)
 8. A composition comprising acompound of claim 1 and a pharmaceutically acceptable carrier.
 9. Amethod of inhibiting a retroviral protease comprising administering aneffective amount of a compound of claim
 1. 10. A method of treating aretroviral infection comprising administering an effective amount of acomposition of claim
 8. 11. A method of preventing replication of aretrovirus comprising administering an effective amount of a compound ofclaim
 1. 12. A method of preventing replication of a retrovirus in vitrocomprising administering an effective amount of a compound of claim 1.13. A method of treating AIDS comprising administering an effectiveamount of a composition of claim
 8. 14. The compound of claim 1represented by the formula

or a pharmaceutically acceptable salt, prodrug or ester thereof.